Documentation: Census 1970
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Publisher: U.S. Census Bureau
Survey: Census 1970
Document: 1970 Census Users' Guide - Part I
citation:
Social Explorer; U.S. Census Bureau; 1970 Census Users’ Guide; U. S. Government Printing Office, Washington, D. C., 1970.
Chapter Contents
1970 Census Users' Guide - Part I
Part II. Population Census Concepts (Concepts 50 through 149)
Introduction
This part of the Census Users Dictionary defines the subject concepts recognized in 1960 and/or 1970 population census tabulations. Concepts and their categories and subcategories are included which appear in tabulations the Census Bureau makes available to users through printed publications, computer tapes, and microfilm or microfiche. Concepts are organized under broad headings such as Education, Financial Wellbeing, etc. Concept definitions indicate or are affected by:
Census questions from which the concept is derived . All concepts (tabulation categories) in this section are derived from responses to one or more census questions. In most cases the concepts are directly comparable to specific response categories. This is true for sex, type of school in which enrolled, year moved into present house, vocational training, etc. In other cases, concepts are derived by combining answers to two or more questions to obtain recodes, for instance, in the determination of labor force status and employment status. Where respondents write in answers, Census Bureau personnel determine a code for each handwritten entry according to specified rules. Occupation, industry, income, and mother tongue are among the concepts derived by coding.

Concept categories carried on basic records, but not on summary tapes . For reasons of cost, report size, usefulness, and reliability, fewer concept categories may be tabulated in a particular matrix than are included on the basic records. For instance, the basic records carry some 70 language codes for the concept mother tongue, but only 20 appear on any summary tape or in any printed report. Similarly, one hundred dollar intervals are used in coding income up to a certain maximum on basic records, but income tabulations employ broader income intervals.

Users may request special tabulations on a contract basis which recognize the full range of concept categories carried on the basic records. However, no information will be furnished which violates the confidentiality of the individual.

The universe to which the concept applies . Not all concepts are tabulated (or carried on basic records) for the entire population. Marital status, for instance, is tabulated for persons 14 years of age and over only, country of origin for the foreign stock only, occupation and industry for the experienced civilian labor force and labor reserve only. Quite a few tabulations are made for persons in households only, excluding groups quarters.

The census(es) to which the concept applies (year) . Most concepts apply both to the 1960 and 1970 population censuses. A few are new in 1970; others have additional or different categories or different universes in 1970.

Whether related questions are complete-count or sample . A very few questions are asked of the entire population--only those basic facts about people such as sex and age which are needed to make an accurate count of persons in each area. These are called complete-count or 100-percent items.

All other items about people are obtained from samples. Sampling permits the collection of data about an area which reflect the characteristics of all persons in the area even though only a small number of individuals were actually questioned. This process also allows the data to be obtained at a much lower cost. Sample cases are weighted to reflect the sampling percentages. In a tabulation based on the 20-percent sample, for example, all cases have weights which average 5; that is, all figures are multiplied by 5 so the final figures will be estimates for all the people in an area rather than just 20 percent of them. Control totals for the multiplication are obtained from the 100-percent items.

In 1960, there was a 25-percent sample; in 1970 there will be a 15-percent sample and a 5-percent sample (in order to reduce the length of the questionnaire for any one individual). Certain questions common to both samples will result in a 20-percent sample. Whether a question is asked of everyone or of a sample of people depends in part on the size of the area for which statistics are to be tabulated and published. Basic population data, including that required for apportionment purposes, is collected on a 100-percent basis and published for city blocks. Data which is considered important for areas as small as census tracts and minor civil divisions is to be collected on a 15- or 20- percent sample basis. The 5-percent sample includes items needed for larger cities, counties, standard metropolitan statistical areas, and States.

The sample percentages for population items included in the 1970 census schedules in comparison with items in the 1960 census are shown below.

Instructions for respondents in mail-census areas .The meaning of concepts and categories derived from replies on mailed-back questionnaires (except where Census editing procedures change the replies) depends on respondents interpretation of the questions, which may or may not be as the Census intended. Some interpretive instructions were included with the questionnaire; these are reflected in the concept definitions included in this dictionary.

In the less densely populated areas of the country, enumeration procedures were the same as the single-stage procedure employed in 1960. In addition, special procedures were used to enumerate persons living in certain types of group quarters, such as college dormitories.

Table 1: 1970 Census Items Compared With 1960 Content
Population Items Complete-count or sample percentage
1960 1970
Relationship to head of household 100 100
Color or race 100 100
Age (month and year of birth) 100 100
Sex 100 100
Marital Status 100 100
State or country of birth 25 20
Years of school completed 25 20
Number of children ever born 25 20
Activity 5 years ago - 20
Employment Status 25 20
Hours worked last week 25 20
Weeks worked last year 25 20
Last year in which worked 25 20
Occupation, industry, and class of worker 25 20
Income last year:    
  Wage and salary income 25 20
  Self-employment income 25 120
  Other income 25 220
Country of birth of parents 25 15
Mother tongue 25 15
Year moved into this house 25 15
Place of residence 5 years ago 25 315
School or college enrollment (public or private ) 25 15
Veteran status 25 15
Place of work 25 415
Means of transportation to work 25 15
Mexican or Spanish origin or descent - 5
Citizenship - 5
Year of immigration - 5
Marital history 25 55
Vocational training completed - 5
Presence and duration of disability - 5
Occupation-industry 5 years ago - 5


Footnotes:

1Single item in 1960; two-way separation in 1970 by farm and nonfarm income.
2Single item in 1960: three-way separation in 1970 by social security public assistance, and all other receipts.
3This item is also in the 5-percent sample but limited to state of residence 5 years ago.
4 Street address included for 1970.
5 In 1960, whether married more than once and date of first marriage; in 1970 also includes whether first marriage ended by death of spouse.

Editing and allocation procedures. Extensive efforts are made to ensure that data collected in the decennial population censuses are complete and accurate. Checking for completeness and consistency of replies began at the local district offices which received the mailed-back questionnaires. The questionnaires were then sent to a central processing center, microfilmed, and fed into an optical scanner (FOSDIC) which reads the information onto magnetic computer tapes. A computer edit program operates on these tapes to check further for completeness and consistency of the data. Certain entries are changed or edited according to fixed instructions. For instance, a person identified as the wife of a household head with a martial status of single is automatically changed to marital status of married, if there is also a head. Where single entries or whole questionnaires are missing, information is allocated for those persons. For example, if earnings were not reported for a male in a certain age group and occupation category who worked 40 or more weeks in 1969, the computer would supply to him the earnings of the last male processed living in the same area with the same age, occupation, and weeks worked characteristics.

Population and density
Total population
The total population of a geographic area recognized in census tabulations comprises all persons enumerated whose usual place of residence at time of census was determined to be in that area.

Citizens of foreign countries temporarily visiting or traveling in the United States or living on the premises of an embassy, legation, etc. Were not enumerated. Resident aliens were enumerated like other Americans.

Population Density
Population density for a geographic area is calculated as the number of persons per square mile of land area (includes dry land; land temporarily or partially covered by water, such as swamps; streams, canals, etc. less than 1/8 mile in width; and lakes, reservoirs, etc. of less than 40 acres).

Place of residence at time of census
Each person enumerated was counted as an inhabitant of his usual place of abode, generally the place where he lived and slept. This place was not necessarily the same as his legal residence, voting residence, etc.

In the application of this rule, persons were not always counted as residents of the places where they happened to be found by the census enumerators or received a census questionnaire in the mail. Persons temporarily away from their usual place of residents--in a hospital, in a hotel, visiting another home, abroad on vacation--were allocated to their homes.

Certain groups in the population were allocated to a place of residence according to special rules. Persons in the Armed Forces quartered on military installations in the United States were enumerated as inhabitants of the places where their installations were located; college students as inhabitants of the places where they resided while attending college; crews of U.S. merchant vessels in harbor as inhabitants of the ports where their vessels were berthed; crews of U.S. naval vessels not deployed to an overseas fleet were enumerated as inhabitants of the home port of the vessel; inmates of institutions as inhabitants of the places where the institutions were located; persons without a usual place of residence and persons staying overnight at a mission, flophouse, jail, etc. as inhabitants of the places where they were enumerated.

American citizens abroad for an extended period (in the Armed Forces, working at civilian jobs, studying in foreign universities, etc.) are not included in the population of the United States or any subnational geographic area, but are tallied as the overseas population.

The place of residence of each individual is then defined in terms of the geographic areas--States, counties, etc.--recognized in census tabulations. The smallest area for which tabulations are generally prepared is the city block in areas with blocks and the enumeration district in other areas.

Urban-rural residence
This is one of the more important breakdowns of the population by geographic residence. The determination of urban-rural residence is made after census results have been tabulated. Geographic areas are classified as urban or rural on the basis of their population size or density at the time of the census.

Urban population
Generally, all persons residing in areas determined to be urbanized areas or in places of 2,500 or more outside urbanized areas. A common breakdown of the urban population is given below.

Population in central cities of urbanized areas
Population in urban fringe of urbanized areas
Population in urbanized areas but not in central cities.

Other urban population outside urbanized areas
Population in places of 2,500 or more outside urbanized areas.

Rural population
Population not classified as urban constitutes the rural population.

Rural farm population
Rural population residing on farms, as ascertained from responses to a question on acreage and dollar sales of farm products.

Persons are classified as residing on farms if they indicate they live on places of 10 or more acres from which sales of crops, livestock, and other farm products amounted to $50 or more in the previous calendar year, or places of less than 10 acres from which sales of farm products amounted to $250 or more.

Rural nonfarm population
Population residing in rural territory but not on farms.

Metropolitan residence
This is another important breakdown of the population by geographic residence. It refers to residence in a standard metropolitan statistical area.

Metropolitan population
Population residing in standard metropolitan statistical areas.

Nonmetropolitan population
Population residing outside SMSAs.

Place of residence five years ago
Ascertained for persons five years of age or over, who were asked to indicate if they lived in this house five years ago or a different house, and, if the latter, to indicate the State (or foreign country, U.S. possession, etc. ) county, and city or town where they lived. (Residence five years ago was to be indicated for the persons usual place of residence.)

In 1970, persons in the 15-percent sample only were asked the question on place of residence five years ago. Persons in the 5-percent sample were asked a less detailed question on State of
residence five years ago. Persons fourteen years and over (in the 5-percent sample) were to indicate if they lived in this State five years ago and if not, to specify the State (or foreign country, U.S. possession, etc.) in which they lived.

Mobility status
Refers to the geographic mobility of the population aged five years and older, comparing the place of residence at time of census with the place of residence five years ago.

Nonmovers (in same house)
Persons living in the same house at time of census as five years ago. Includes those who had moved but returned.

Movers (mobile population)
Persons living in a different house in the United States at time of census than five years ago. Includes only persons for whom sufficient information concerning place of residence five years ago is obtained. (Missing information is supplied where available from other members of the persons family.) A common breakdown of the mobile population is given below.

Intracounty movers
Persons living in a different house but in the same county at time of census as five years ago. Includes those who had moved from the county but returned.

Intercounty movers (migrants)
Persons living in a different county at time of census than five years ago. The migrant population is commonly broken down into intercounty migrants, same State and intercounty migrants, different State .

Abroad
Persons residing in a foreign country or an outlying area of the U.S. five years ago. In 1960, persons living in Alaska or Hawaii in 1955 but in other States in 1960 were classified as living in a different State in 1955.

Moved, place of prior residence not reported
Includes persons living in a different house at time of census than five years ago, but did not provide sufficient or consistent information about their previous place of residence.
Also includes persons who gave no indication whether their place of residence at time of census was different from or the same as their place of residence five years ago, but who in response to the question on year moved into present house indicated that they moved into their present house within the five-year period before the census.

Year moved into present house
Persons were asked to indicate the most recent move they made by one of several time period categories. In 1970 the categories are: 1969-1970, 1968, 1967, 1965-1966, 1960-1964, 1950- 1959, 1949 or earlier, and always lived in this house or apartment. The categories were comparable in 1960.

Persons who moved back into the same house or apartment where they lived previously were asked to give the year when they began the present occupancy. Persons who moved from one apartment to another in the same building were asked to give the year they moved into the present apartment.

Age and sex
Age is usually determined in completed years as of the time of enumeration from replies to a question on month and year of birth. (Only year of birth by quarter is actually carried on census basic records.) Age is estimated from other information reported in the schedule if the respondent fails to indicate birth date. Age is tabulated by single years from under 1 year, 1, 2, 3, . . . to 98, 99, and 100 years or more; and by many different age groupings, such as five-year age groups. Median age is calculated as the value which divides the age distribution into two equal parts, one-half the cases falling below this value, one-half above. Median age is generally computed from the age intervals or groupings shown in the particular tabulations, except that median age in tabulations of single years of age is based on five-year age groups.

Sex
Males
Females
Sex ratio is calculated as the number of males per 100 females.

Race
refers to the division of the population into white, Negro, and several other racial categories. These racial categories do not correspond to strict scientific definitions of biological stock. Persons were asked to indicate their race by selecting one of the following: White; Negro or Black; Indian (American); Japanese; Chinese; Filipino; Hawaiian; Korean; Other (specify). (In Alaska, Hawaiian and Korean were omitted and Aleut and Eskimo were added.)

Written entries in the other category are checked against a list of possible written entries.

This list indicates whether the written entry should remain in the other category or be correctly classified in one of the printed categories. If the written entry does not appear on the list, the entry remains in the other category.

White population
Includes persons who indicated their race as white. Also includes persons who indicated the other race category and furnished written entries that should correctly be classified in the white category.

All other races population
Includes all persons who did not indicate their race as white or did not have their entry classified as white.

Negro and other races population
Includes persons who indicated their race as one of the following:

Includes persons who indicated their race as Negro or Black. Also includes persons who indicated the other race category and furnished a written entry that should be classified as Negro or Black.

American Indian
Includes persons who indicated their race as Indian (American) or reported an Indian tribe. In 1970 persons who indicated their race as American Indian were also asked to indicate their tribe.

Japanese
Includes persons who indicated their race as Japanese and persons with written entries that should be classified as Japanese.

Chinese
Includes persons who indicated their race as Chinese and persons with written entries that should be classified as Chinese.

Filipino
Includes persons who indicated their race as Filipino and persons with written entries that should be classified as Filipino.

Hawaiian and Korean
Includes persons in all the States (excluding Alaska) who indicated their race as Hawaiian or Korean. Also includes persons in the States who had written entries that should be classified as Hawaiian or Korean. In Alaska, persons who are Hawaiian and Korean are included in the other races category.

Aleut and Eskimo
Includes persons in the State of Alaska who indicated their race as Aleut or Eskimo. In the other 49 States persons who indicated Aleut and Eskimo are included in the other race category.

Other races population
Includes persons who indicated the other race category and had a written entry that is not classified as another category.

During publication this is often considered as a residual category and includes statistics for all races not shown separately.

Mixed parentage
Persons indicated racial mixture are classified according to the race of the father, if he was present in the household and his race was one of the races entered for the person. If the fathers race cannot be determined, the first race listed is used.

Nativity, parentage, ethnic background
Nativity
Ascertained from a question on place of birth (State, foreign country or U.S. possession) or, in certain cases, parents place of birth. The population is classified into two major groups: native and foreign born. Place of birth was to be reported for the mothers usual place of residence, rather than the location of the hospital, etc., where birth occurred.

Native population
Includes persons born in the United States, Puerto Rico, or a possession of the United States. Also included are persons who, although they were born in a foreign country or at sea, have at least one native American parent.

The native population is classified by State of birth and related categories. Codes for each State and major U.S. possession are carried on census basic records. However, detailed tabulations of State of birth are not prepared. Rather, a more general categorization of State of birth related to State of residence , which is useful for migration analysis, is presented. The complete set of categories is as follows:

Natives born in state of residence (persons living in state of birth)
Persons born in the State in which they were residing at time of enumeration.

Natives born in other states
Persons born in a State other than one in which they were residing at time of enumeration. This category is further broken down into region of birth in some tabulations.

Natives born in outlying area of U.S. (at Sea, etc.)
Census basic records carry natives born in outlying areas of U.S. as a separate category from natives born at sea or abroad of American parents.

Puerto Rican stock
Includes persons known to have been born in Puerto Rico and other persons with one or both parents born in Puerto Rico. Also referred to as natives of Puerto Rican origin or as persons of Puerto Rican birth or parentage.

Natives State of birth not reported
Persons whose place of birth was not reported are assumed to be native in the absence of contradictory information.

Foreign born population
Includes all persons not classified as native.

Parentage
Information obtained from a question on birthplace (country) of mother and father is used to classify the native population of the United States into two categories: native of native parentage and native of foreign or mixed parentage.

Native of native parentage
Includes native persons., both of whose parents are also native of the United States.

Native of foreign or mixed parentage
Includes native persons, one or both of whose parents are foreign born.

Foreign stock
Includes the native population of foreign or mixed parentage and the foreign born population. The foreign stock is classified by country of origin.

Country of origin and country of birth
The foreign stock is classified by country of origin--either country of birth or country of birth of parents. Separate distributions are shown for the foreign born (based on country of birth) and for the native population of foreign or mixed parentage (based on country of birth of parents). Native persons of foreign parentage whose parents were born in different foreign countries are classified according to the fathers country of birth.

Countries specified in the distributions comprise those officially recognized by the U.S. State Department at the time of the census. (Respondents were asked to report country of birth according to international boundaries recognized by the U.S. at the time of enumeration and to distinguish between Ireland and Northern Ireland. ) Over 80 countries are separately shown in some country of origin tabulations.

Spanish-American population
In the 1960 census, selected tabulations were prepared for the Puerto Rican population in areas outside the five Southwestern States where Spanish surname population was identified.

In the 1970 census, the Spanish-American population is defined differently according to the sample a person is enumerated in and his State of residence. All tabulations except those for 5-percent data are based upon a 15-percent sample, defined as follows:

a. In New York, New Jersey and Pennsylvania, persons of Puerto Rican stock , (See 61.131 above).

b. In the five southwestern States (Arizona, California, Colorado, New Mexico, and Texas), persons of Spanish language (see 67.1 below) or persons not of Spanish language but of Spanish surname identified by matching with a list of about 8,000 such names.

c. In the remaining States, persons of Spanish language . (See 67.1 below.)

Tabulations of 5-percent data are for persons who report Spanish origin or descent including Mexican, Puerto Rican, Cuban, Central or South American, and other Spanish. Spanish origin or decent is ascertained by means of a 5-percent sample question new with the 1970 census.

Citizenship
Not asked in 1960. In 1970 ascertained for persons born abroad, who were asked if they were naturalized citizens, aliens, or born abroad of American parents (native). The total population is then classified as native citizens , naturalized citizens , or aliens .

Year of immigration
Not asked in 1960. In 1970 ascertained for the foreign born who were asked to indicate when they came to the United States to stay. The reply is categorized by several time periods: 1965-70, 1960-64, 1955-59, 1950-54, 1945-49, 1935-44, 1925-34, 1915-24 and before 1915.

Mother tongue
In 1960, only the foreign born were asked what language was spoken in the persons home before he came to the U.S. If a person reported more than one language, the code assigned was the mother tongue reported by the largest number of immigrants from his native country in the 1940 census.

In 1970, persons, regardless of place of birth, were asked what language, other than English, was usually spoken in the persons home when he was a child. If more than one foreign language were spoken, respondents were to indicate the principal one.

Tabulations are presented for over 20 common European languages, plus American Indian languages, Chinese, Japanese, and Arabic. Over 70 language categories are carried on census basic records.

Spanish language population
Persons who report Spanish as their mother tongue, as well as persons in families in which the head or wife reports Spanish as his or her mother tongue.

Education
Enrollment status
In 1960, ascertained for persons 5 to 34 years of age, who were classified as enrolled in school if they attended regular school or college at any time since February 1, 1960. (Attendance at a nursery school, business or trade school, or adult education classes was not to be counted; regular schooling included kindergarten and schooling leading to an elementary school certificate, high school diploma, or college degree.) Persons enrolled in a regular school who did not actually attend because of illness, etc. were classified as enrolled in school. In 1970, ascertained for persons 3 years and older, who are classified as enrolled in school if they attended regular school or college at any time since February 1, 1970. (Regular schooling includes nursery school, kindergarten, and schooling leading to an elementary school certificate, high school diploma, or college degree.)

Level and year or grade of school in which enrolled
Persons enrolled in school were asked the year or grade in which enrolled up to 6 or more years of college. In 1960, enrollment was classified into four levels with separate years or grades identified within each level as indicated below. In 1970, enrollment is classified as in 1960 with the addition of nursery school.

Nursery school
Identified in 1970, but not in 1960.

Kindergarten
Elementary school
Includes grades 1 through 8, identified separately in some tabulations. (Persons enrolled in a junior high school are classified as enrolled in elementary school or high school according to year in which enrolled.)

High school
Includes grades 9 through 12, identified separate] y in some tabulations. (See elementary school, above, for treatment of junior high school enrollment.)

College
Includes 1 through 5 academic years and 6 years or more, identified separately in some tabulations. College enrollment is defined to include enrollment in junior or community colleges, regular 4-year colleges, and graduate or professional schools.

Type of school in which enrolled
Persons enrolled in school are classified by type of school in terms of public or private, as indicated below.

Public school enrollment
Includes persons attending schools controlled and supported primarily by local, State, or Federal governmental agencies.

Private school enrollment
Includes persons attending schools controlled and supported mainly by religious organizations (parochial schools) or private persons or organizations. In 1970, parochial school enrollment and other private school enrollment are identified as separate categories for each level of school except college.

Years of school completed
In 1960, ascertained for persons 5 years of age and over; in 1970, for persons 3 years of age and over, who were asked the highest grade or year of regular school they ever attended up to 6 or more years of college, Persons attending school were asked the year they were completing. Persons were also asked whether they finished the year specified as the highest grade attended (or were attending that year).

The number tabulated in each category of years of school completed includes persons who report completing that grade or year plus those who attended but did not complete the next higher grade. A common breakdown is no school years completed; 1-4, 5-6, 7, 8 years elementary; 1-3, 4 years high school; 1-3, 4 academic years or more college. Single years of the highest grade attended are carried on census basic records. Tabulations are commonly produced for particular age groups such as persons 14 and over, persons 25 and over, persons 14 to 24 not enrolled in school.

Median school years completed is calculated as the value which divides the population in half, Years of school completed statistics are converted into a continuous series: the first year of high school becomes grade 9, the first year of college grade 13, etc. Persons who have completed a given year are assumed to be evenly distributed from .0 to .9 of the year. For example, persons who have completed the 12th grade are assumed to be evenly distributed between 12.0 and 12.9.

Vocational training
Not asked in 1960. In 1970, ascertained for persons 14 to 64 years of age who were asked whether they ever completed a vocational training program; for example, in high school, as an apprentice, in a school of business, nursing, or trades, in a technical institute, or an Armed Forces school. Respondents were also asked to indicate the main field of such training as follows: business, office work; nursing, other health fields; trades and crafts; engineering or science technician, draftsman; agriculture or home economics; other field. Vocational training does not include courses received by correspondence, on-the-job training, or Armed Forces training not useful in a civilian job.

Marital status and history
Marital status
Persons were asked whether they were now married, widowed, divorced, separated, or never married.

Single (never married)
Includes persons whose only marriage was annulled.

Ever married
Includes persons married at time of enumeration including separated, plus widowed and divorced.

Now married
Includes persons married only once plus persons who remarried after being widowed or divorced. Enumerators were instructed to report persons in common- law marriages as married.

Married, spouse present
Persons whose spouse was enumerated as a member of the same household, even though he or she may have been temporarily absent on vacation, visiting, in hospital, etc. This category is recorded as a sample item only. The number of married males, wife present by definition equals the number of married females, husband present, but may not do so in tabulations of the sample because of the method used to weight information on persons enumerated in the sample portion of the census.

Married, spouse absent
Separated
Persons who reported they were separated. (Includes persons deserted or living apart because of marital discord, as well as legally separated persons.)

Married, spouse absent, other
Married persons whose spouse was not enumerated as a member of the same household, excluding separated. Includes those whose spouse was employed and living away from home, whose spouse was absent in the Armed Forces, or was an inmate of an institution, all married persons living in group quarters, and all other married persons whose place of residence was not the same as that of their spouse. This category is recorded as a sample item only,

Widowed
Divorced
Persons legally divorced.

Times married
Ascertained for persons ever married, who were asked if they had been married once or more than once.

Age at first marriage
Shown in completed years for persons ever married. Ascertained from a question on month and year of marriage if married once, and month and year of first marriage if married more than once.

Termination of first marriage
Not asked in 1960, In 1970, persons ever married who reported they had been married more than once were asked if their first marriage ended because of death of spouse. This information is used in conjunction with current marital status to classify the entire ever married population by marital history as follows.

Widowed only
Persons married only once who were widowed at the time of enumeration, plus persons married more than once whose first marriage ended by the death of the spouse and who were not divorced. (In printed reports, this group is combined with 76.3 to represent known to have been widowed

Divorced only
Persons married only once who were divorced; plus persons married more than once whose first marriage did not end by the death of the spouse and who were not widowed. (In printed reports, this group is combined with 76.3 to represent known to have been divorced. )

Widowed and divorced
Persons married more than once whose marital status at the time of enumeration was widowed and whose first marriage did not end in death of spouse, or whose marital status was divorced and whose first marriage ended in death of spouse.

Neither widowed nor divorced
All other married persons married only once.

Fertility
Children ever born
In 1960 total live births of women age 14 or over (in some tabulations 15 or over) who reported they were ever married. In 1970, total live births are ascertained (and carried on census basic records) for all women age 14 or over, regardless of marital status. (Tabulations generally are still for married women). Respondents were asked to indicate number of children ever born as none, 1, 2, 3, . . up to 12 or more. (For purposes of computing total children ever born, the terminal category is given a mean value of 13. )

The questionnaire instructed respondents to exclude stepchildren or adopted children. Enumerators were instructed to include children born to the woman before her present marriage, children no longer living, and children away from home, as well as children still at home.

This information is used in fertility analysis. The number of children ever born per 1,000 women of several age groups is calculated for all women and for ever married women.

Fertility ratio
This is calculated as the number of children under 5 years of age per 1,000 women 15 to 49 years old. (The base includes single women as well as women ever married. )

Living arrangements
Household/group quarters membership
All persons enumerated are classified as living in households or group quarters.

Household membership
All persons occupying a single housing unit (see Part III, Housing Concepts) are referred to as a household. Average population per household is calculated as the population in households divided by the number of households. (See also persons per unit in Part III. )

Group quarters membership
All persons who are not members of households are regarded as living in group quarters. (See Part III, Housing Concepts.)

Quarters occupied by 5 or more persons unrelated to the head of the household are called group quarters. Quarters with no designated head but with 6 or more unrelated persons are also group quarters.

Some quarters occupied by only one or two persons may also be group quarters. For example, one to five persons occupying a surgical ward of a general hospital, who have no usual residence elsewhere, are in group quarters, as are students living in dormitories. Institutional quarters occupied by one or more patients or inmates are institutional group quarters.

All members of group quarters are classified as either secondary individuals or as inmates of institutions. Group quarters members are classified by type of group quarters as shown below.

Inmates of institutions
Persons for whom care or custody is being provided in institutions. Includes inmates of mental hospitals, inmates of homes for the aged, and inmates of other institutions . Census sample basic records include type of institution categories.

Other persons in group quarters (Noninmates)
Further classified as shown below. (See also secondary individual .)

Persons in rooming houses
In addition to rooming and boarding houses, this category includes group quarters in ordinary homes, tourist homes, residential clubs, and Ys. (Not all persons living in these types of quarters are classified as living in group quarters; some are classified as living in housing units. ) (See Concept No. 151.1, housing units.)

Persons in military bar racks
Quarters for military personnel which are not divided into separate housing units. In 1960, data on persons in such quarters were shown only for men. In 1970, they will include both men and women as well as being shown separately for men.

Persons in college dormitories
Includes dormitories and fraternity and sorority houses.

Persons in other group quarters
Includes general hospitals (including quarters for staff), missions or flophouses, ships, religious group quarters such as convents, dormitories for workers (such as logging camps or quarters for migratory workers). In 1960, women in military barracks were also classified as in other group quarters in tabulations. In 1970, resident staff members of institutions (persons occupying group quarters on institutional grounds who provide care or custody for inmates) are classed as in other group quarters in tabulations (but carried separately on census basic records); in 1960, such persons were shown as a separate category.

Household relationship
Ascertained from replies to a question on relationship to household head. Respondents were asked if they were the head of household, wife of head, son or daughter of head, other relative of head (and to specify exact relationship), roomer, boarder, lodger, patient or inmate, other not related to head (and to specify exact relationship).

Head of household
One person in each household was designated as the head, that is, the person who was reported as the head by the members of the household. However, if a married woman living with her husband was reported as the head, her husband is considered as the head for the purpose of simplifying the tabulations.

Two types of household head are distinguished -- head of a family and primary individual. A family head is a household head living with one or more persons related to him by blood, marriage, or adoption. A primary individual is a household head living alone or with non-relatives only.

Wife of head
A woman married to and living with a household head. This category includes women in common-law marriages as well as women in formal marriages. In complete- count tabulations, the number of wives of head is the same as the number of husband-wife households and the number of husband-wife families. The number does not equal the number of married women, husband present, since it excludes those married women whose husbands are not household heads (as in subfamilies, Concept No. 81.111).

Child of head
A son, daughter, stepchild, or adopted child of the head of the household of which he is a member, regardless of the child's age or marital status. The category excludes sons-in-law and daughters-in-law. (Also see own children Concept No. 84.1. )

Other relative of household head
Household member related to head by blood, marriage, or adoption, but not included specifically in another relationship category. In the sample they are classified as grandchild of head, parent of head or son or daughter-in-law of head, brother or sister of head, parent-in-law of heads or brother or sister-in-law of head and other relative of head, and are identified as separate categories in some tabulations.

Nonrelative of household head
Any household member not related to the head; further classified as lodger, resident employee, and friend or partner. These categories are recorded as sample items only.

Lodger
Persons identified as roomer, boarder, lodger. In the sample it includes foster children not already identified as roomer, boarder or lodger.

Resident employee
An employee of the household (such as maid, cook, hired farm hand, companion, nurse), who usually resides in the housing unit. Also includes the employees relatives living in the housing unit.

Friend or partner
This is a residual category, including all persons not identified as roomer, boarder, or lodger or resident employee. In tabulations, it is often combined with roomer, boarder, lodger.

Family structure
Family/unrelated individual status
All persons enumerated are classified as family members, unrelated individuals, or inmates of institutions.

Family
Two or more persons living in same household who are related by blood, marriage, or adoption. (No families are recognized in group quarters. ) All persons living in a household related to each other are regarded as one family. For instance, a son of the head and his wife living in the household are treated as part of the heads family.

The number of families does not necessarily equal the number of households, since not all households include families. Families are classified in the complete-count basic records by family size or number of persons in a family from 2 persons to 35 persons. Average number of persons per family is calculated.

Family (primary)
Family whose head is also the household head. In 1970, primary families are simply termed families.

Subfamily
Married couple with or without own children, or one parent with one or more own children (parent-child group), living in a housing unit and related to the household head, but excluding the head (for example, a son, his wife and children, living with the household head). Since subfamily members are counted as part of the heads (primary) family, too, the number of subfamilies is not included in the count of families per seer in any tabulations for families. Census basic records include categories of sub-families by family type.

Secondary family
In 1960, a family in a household whose head was not related to the household head. In 1970, secondary families are not recognized (since there are so few); persons formerly classed as secondary family members are classed as secondary individuals.

Unrelated individual
Persons not living with relatives, but living in a household entirely alone or with one or more persons not related to him, or living in group quarters (excepting inmates of institutions).

Primary individual
Household head living alone or with nonrelatives only. The number of primary individuals living alone equals the number of one-person households.

Secondary individual
Unrelated individual who is not a household head or who lives in group quarters (excepting inmates of institutions).

Family Type (family head)
Families (primary) and subfamilies are classified by type according to sex and marital status of the family head as indicated below.

Husband-wife families
The head and his wife were enumerated as members of the same household.

Other families with male head
Family with male head, but no spouse of head present.

Families with female head
Family where the head is female and there is no spouse of head present.

Married couples
Husband and his wife were enumerated as members of the same household. (No married couples were recognized in group quarters.) This category is recorded as a sample item only. The number of married couples equals the number of married males , wife present . By definition it also equals the number of married females, husband present , but may not do so in tabulations because of the method used to weight information on persons enumerated in the sample portion of the census. The number of married couples bears no necessary relationship to the number of families, since some married couples may constitute subfamilies of household heads families, while some families may be headed by single individuals.

Married couples with own household
In 1960, the same as husband-wife primary families. In 1970, the same as husband-wife families.

Married couples without own household
In 1960, two subcategories were recognized: married couples without own household living with nonrelatives, i.e., husband-wife secondary families; and married couples without own household living with relatives, i.e., subfamilies with both spouses present. In 1970, only the second category of married couples without own household living with relatives is recognized.

Children
Own children
Never-married persons under 18 who are son, daughter, stepchild, or adopted child of the family head.

Related children
Own children under 18 plus all other family members under 18 (regardless of marital status) related to the family head.

Military status and history
Military status
Ascertained as of time of enumeration for all persons 14 years of age and over. This information is used in connection with labor force concepts.

Civilians
Persons 14 and over not in the Armed Forces at the time of enumeration.

In the Armed Forces
Persons 14 and over on active duty with the U.S. Army, Navy, Air Force, Marine Corps, or Coast Guard.

Veteran status and history
Veterans are civilian males (persons on active duty at the time of enumeration are excluded), 14 years of age and over, who have served in the Armed Forces of the United States, regardless of whether their service was in war or peace-time. Veterans in 1960 were asked whether they served in World War I (April 1917 to Nov. 1918), World War II (Sept. 1940 to July 1947), the Korean War (June 1950 to Jan. 1955), and any other time, including present service. Persons who reported serving in both the Korean War and World War II were tabulated as a separate group. All others who reported more than one period of service were classified according to the most recent wartime period of service reported.
In 1970, veterans were asked whether they served in World War I, World War H, the Korean War, the Vietnam Conflict (August 1964 to present), and any other time.

Work patterns: labor force and employment concepts
Labor force status
Ascertained for persons 14 years of age and over as of the calendar week prior to data of enumeration (reference week). In 1970, most labor force tabulations will be presented for persons 16 years and over.

Labor force
Includes persons classified as employed or unemployed plus members of the Armed Forces.

Civilian labor force
All persons employed or unemployed, excluding members of the Armed Forces.

Experienced civilian labor force
Employed plus experienced unemployed.

Not in labor force
All persons 14 and not classified as members of the labor force, including persons doing only incidental unpaid work on a family farm or business (less than 15 hours during the reference week). Most of the persons in this category are students, housewives, retired workers, seasonal workers enumerated in an off season who are not looking for work, inmates of institutions, or persons who cannot work because of long-term physical or mental illness or disability.

Labor reserve
Persons classified as not in the labor force during the reference week, but who indicated in reply to the question on year last worked that they did work within the ten-year period preceding the census.

Employment status
Ascertained for persons 14 years of age and over from replies to several questions relating to work activity and status during the reference week. These questions were: Did this person work at any time last week (include part-time work such as Saturday job or helping without pay in family business or farm and active duty in the Armed Forces; exclude housework, school work, or volunteer work)? How many hours did he work last week (at all jobs)? Does this person have a job or business from which he was temporarily absent either because of illness, vacation, labor dispute, etc., or because he was on layoff last week? Has he been looking for work during the past four weeks, and if so, was there any reason why he could not take a job last week?

Employed
Civilians 14 years and over who during the reference week were either at work -- who did any work for pay or profit or worked without pay for 15 hours or more on a family farm or business; or with a job but not at work -- were temporarily absent because of reasons such as illness, vacation, etc. The two categories, at work and with a job but not at work, are shown separately in some tabulations.

Unemployed
In 1960, civilians 14 years and over who were neither at work nor with a job but not at work during the reference week but were looking for work within the past 60 days. (Examples of looking for work include registering at an employment office, writing letters of application, etc.) Persons waiting to be called back to a job from which they were laid off or furloughed were also counted among the unemployed.

In 1970, civilians 14 years and over who were neither at work nor with a job but not at work within the past 4 weeks and were available for work during the reference week. Persons waiting to be called back to a job from which they had been laid off or who were waiting to report to a new wage or salary job within 30 days were counted among the unemployed. (Availability for work is indicated by replies to a question -- new in 1970 -- whether there was any reason why the respondent could not take a job last week.)

Experienced unemployed
Those unemployed who indicate in reply to the year last worked question that they have worked at some time in the past.

Unemployment rate
Represents the number of unemployed as a percent of the civilian labor force. Unemployment rates shown for occupation and industry groups are based on the experienced civilian labor force, since occupation and industry cannot be ascertained for those unemployed who have never worked.

Hours worked
Ascertained for persons 14 years of age and over who indicate they were at work during the reference week. Respondents were asked how many hours they worked last week at all jobs, excluding time off and including overtime or extra hours. The information was collected for the following categories: 1 to 14 hours, 15 to 29 hours, 30 to 34 hours, 35 to 39 hours, 40 hours, 41 to 48 hours, 49 to 59 hours, 60 hours or more.

Tabulations are shown for hours worked by several categories. The information is also used to classify employed persons at work into full-time employed (persons working 35 hours or more during the reference week) and part-time employed (persons working less than 35 hours during the reference week).

Weeks worked
Ascertained for persons 14 years of age and over who worked at all during the calendar year preceding the census. Two questions on this subject were asked: Last year (1969), did this person work at all, even for a few days? If yes, then How many weeks did he work in 1969, either full-time or part-time? Paid vacations, paid sick leave, and military service are counted as weeks worked. The following time categories were presented: 13 weeks or less, 14 to 26 weeks, 27 to 39 weeks, 40 to 47 weeks, 48 to 49 weeks, and 50 to 52 weeks.
It should be noted that the determination of weeks worked during the previous year was essentially independent of the determination of the current employment status of the respondent.

Year last worked
Ascertained for persons 14 years of age and over who were not classified in one of the following categories: at work,Armed Forces,with a job but not at work. Respondents were asked when they last worked at all, even for a few days (including any work for pay or profit, unpaid work on a family farm or business, and active service in the Armed Forces), for several time period categories. For 1960, these were 1960, 1959, 1955 to 1958, 1950 to 1954, 1949 or earlier, and never worked; for 1970 categories were 1970, 1969, 1968, 1964 to 1967, 1960 to 1963, 1959 or earlier, and never worked.

Year last worked was tabulated for persons classified as not in the labor force or unemployed.

Disability status
Not asked in 1960. In 1970, ascertained for persons age 14 to 64. Respondents were asked if they had a health condition or disability which limited the kind or amount of work they could do at a job and whether their health prevented them from doing any work at all. Persons who answered yes to either or both questions are classified as disabled ; persons who responded that they had a disability but were not prevented from doing any work at all as disabled, able to work; persons who responded their health prevented them from doing any work at all as disabled , cannot work .

Duration of disability
Not asked in 1960. In 1970, persons who indicated they had a disability affecting the kind or amount of work they could do on a job were asked how long they had been disabled: less than 6 months, 6 to 11 months, 1 to 2 years, 3 or 4 years, 5 to 9 years, 10 years or more.

Work patterns: occupation, industry, and related concepts
Occupation
Ascertained for persons 14 years of age and over in the experienced civilian labor force or in the labor reserve. Employed persons were to report the occupation at which they worked the most hours during the reference week. The experienced unemployed and persons in the labor reserve were to report their last occupation. (Excludes the small number of experienced unemployed persons who last worked more than 10 years ago).

In 1960, respondents were asked to describe what kind of work they were doing, for example, 8th grade English teacher, farmer, grocery checker, etc. In 1970, respondents were asked to give this information and, in addition, to specify their most important activities on duties on the job, such as types, cleans building, sells cars, etc., and to indicate their job title. This additional information was requested so that occupation can be coded more accurately.

Information supplied by respondents is assigned an occupation code by clerks. In 1960, there were 11 major occupation groups and an occupation not reported category (listed below). The major occupation groups were divided into 494 items: 297 specific occupations and 197 subcategories which were mainly industry distributions of 13 specific occupations. Tabulations which present the complete range of specific occupations and subcategories are referred to as detailed occupation tabulations. Other tabulations present intermediate levels of classification, combining specific occupations and subcategories into broader groupings.

The occupation classification scheme employed in 1960 is fully described in Bureau of the Census, 1960 Census of Population, Classified Index of Occupations and Industries, available from the Superintendent of Documents.

1960 Major Occupation Groups
Professional, technical and kindred workers

Farmers and farm managers

Managers, officials, and proprietors, except farm

Clerical and kindred workers

Sales workers

Craftsmen, foremen, and kindred workers

Operatives and kindred workers

Private household workers

Service workers, except private household

Farm laborers and foremen

Laborers, except farm and mining

Occupation not reported

For 1970, there are 12 major groups instead of 11 as in 1960. The new major group, entitled Transport Equipment Operatives, is made up of bus drivers, parking attendants, truck drivers, and others similarly employed. The categories comprising the new major group were moved from the 1960 major group Operatives and Kindred Workers, affording a basis for comparability.

A second revision (shown below) was the recasting of the arrangement of the major groups to reflect four broad occupational areas. The major groups and the occupational areas to which they relate are as follows:

1970 Major Occupational Groups Areas    Occupational Areas

Professional, technical, and kindred workers    White collar workers
Managers and administrators, except farm
Sales workers
Clerical and kindred workers

Craftsmen and kindred workers    Blue collar workers
Operatives, except transport
Transport equipment operatives workers
Laborers, except farm

Farmers and farm managers    Farm workers
Farm laborers and farm foremen

Service workers, except private household    Service workers
Private household workers

A third revision to the major groups relates to the processing of the data. Individuals who did not report an occupation were allocated to a major group through an allocation matrix based on selected demographic and economic characteristics. Thus, major group totals in 1970 include persons allocated to the major groups.

Fourth, instead of having the categories within each major group listed alphabetically, sub-grouping, or occupation families, have been established in several major groups. For example, the service workers group, to clarify its content, has been reclassified into 5 subcategories -- cleaning service, food service, health service, personal service, and protective service.

The Classified Index of Occupations to be used in the 1970 census is scheduled to be published this year. Copies will be available from the Superintendent of Documents of the Government Printing Office. Also, see the Statistical Reporter, December 1969, for a relevant article and occupations listing.

Industry
Ascertained for persons 14 years of age and over in the experienced civilian labor force or in the labor reserve. Employed persons were to report the job at which they worked the most hours during the reference week. The experienced unemployed and persons in the labor reserve were to report the job they last held. Respondents were asked the name of their employer (company or organization); what kind of business or industry this was (describe activity at location where employed, for example, county junior high school, auto assembly plant, retail supermarket, farm, etc.); and to indicate whether this was primarily manufacturing, wholesale trade, retail trade, or other. The name of employer is a basic tool in coding industry, since coders refer to lists of establishments showing their industrial classification from the quinquennial Economic Censuses.

Information supplied by respondents is assigned an industry code. In 1960, there were 12 major industry groups and an industry not reported category (listed below). These groups were further classified into 150 specific categories. Intermediate levels of industry classification scheme were presented in some tables. The 1960 industry classification scheme is described fully in Bureau of the Census, 1960 Census of Population, Classified Index of Occupations and Industries, available from the Superintendent of Documents.

Agriculture, forestry, and fisheries

Mining

Construction

Manufacturing

Transportation, communication, and other utilities

Wholesale and retail trade

Finance, insurance, and real estate

Business and repair services

Personal services

Entertainment and recreation services

Professional and Related services

Public administration

Industry not reported

For the 1970 census, the Industry Classification System, like that for occupation, has been revised. This system is designed for use in classifying the industry returns for the 1970 population census and demographic surveys to be conducted by the Bureau of the Census during the decade of the seventies. The system is patterned after the classification outlined in the 1967 edition of the Standard Industrial Classification Manual (S.I.C.).

For 1970, there are 226 uniquely identified groups in the classification in contrast to the 150 groups in the 1960 classification. These 76 additional codes stemmed from revisions to 24 specific 1960 industry categories. For the most part, the changes represent establishment of smaller, more homogeneous groups. The 1960 Industry Not Reported category has been eliminated. Cases where codes are not reported will be allocated to the major groups.

The 1970 Classified Index of Industries will be published sometime this year. Copies may be obtained from the Superintendent of Documents. Also, see the Statistical Reporter, April 1969, for a relevant article and industries listing.

Class of worker
Ascertained for persons 14 years of age and over in the experienced civilian labor force or in the labor reserve. Employed persons were to report class of worker for the job at which they worked the most hours during the reference week. The experienced unemployed and persons in the labor reserve were to report class of worker for the job last held. Respondents were asked to indicate class of worker by one of several categories shown below. Note that the determination of class of worker was independent of occupation and industry classification but refers to the same job.

Private wage and salary workers
Includes persons who indicated they were employees of a private company, business, or individual, working for wages, salary, or commissions, and those noted in 97.3 below.

Government workers
Includes persons who indicated they worked for a governmental unit (Federal, State, or local). In 1970, employees of the Federal government, State governments, and local governments were ascertained as separate subcategories.

Self-employed workers
Persons who indicated they were self-employed in own business, professional practice, or farm. In 1970, respondents were asked to specify whether their own business was incorporated or unincorporated. Those who said the business was incorporated are classified as private wage and salary workers rather than as self-employed.

Unpaid family worker
Persons who indicate they worked without pay in a family business or farm (the business or farm was operated by a family relative).

Activity five years ago
Asked in 1970 for the first time and ascertained for persons 14 years of age and over who were asked if, in April, 1965, they were working at a job or business (full or part-time), if they were in the Armed Forces, or if they were attending college.

Occupation five years ago
Asked in 1970 for the first time and ascertained for persons 14 years of age and over who indicated they were working at a job or business five years ago. Respondents were asked to specify their occupation or kind of work in 1965. The questions on major activities and job titles were not included. Occupation five years ago is then coded as for current occupation.

Industry five years ago
Asked in 1970 for the first time and ascertained for persons 14 years of age and over who reported they were working at a job or business five years ago. Respondents were asked to specify the industry for which they worked five years ago. The supplementary questions on name of employer and manufacturer, wholesaler, etc., were not included. Industry five years ago is then coded as for current industry.

Class of worker five years ago
Asked in 1970 for the first time and ascertained for persons who reported they were working at a job or business five years ago. The information was obtained from a question which asked if they were an employee of a private company or government agency or self-employed or an unpaid family worker.

Work patterns: place of work and means of transportation to work
Place of work
Ascertained for persons 14 years of age and over who reported working at some time during the reference week, (except those on leave, sick, etc.). They were asked where they worked last week. (Persons who worked at more than one job are to report place of work for the job at which they worked the greatest number of hours; persons who traveled in their work or worked in more than one place are to report where they began work if they reported to a central headquarters, or where they worked the most hours.)

In 1960, respondents were to specify city or town, county and State where they worked. Place of work replies were tabulated in various ways by the workers place of residence; for example, working in same county or different county as workers place of residence; working in same State, contiguous State, or noncontiguous State as place of residence. Place of work by place of residence was also tabulated for universal area code areas.

In 1970, respondents were to specify State, zip code, county, city or town, and exact street address where they worked. Tabulations similar to 1960 will be produced. In addition, since street address was ascertained, place of work may be coded to small geographic areas such as tracts or enumeration districts and made available on that basis if requested as a special tabulation.

Means of transportation to work
Ascertained for persons 14 years of age and over who reported working during the reference week, including Armed Forces personnel, Respondents were asked that principal mode of travel or type of conveyance used to get to their place of work on the last day they worked.

In 1960, the categories were private auto or car pool, railroad, subway or elevated (the latter two categories were combined in tabulations); bus or streetcar: taxicab. other means (taxicab was included in other means in tabulations); walked only; worked at home.

In 1970, the categories are driver, private auto; passenger, private auto; bus or streetcar; subway or elevated ; railroad; taxicab, walked only; worked at home; other means.

Financial well being income and poverty concepts
Total income
Ascertained for all persons 14 years of age and over for the preceding calendar year, even if they had no income. Total income is the sum of the dollar amounts of money respondents reported receiving (best estimate if exact amount not known) as wages or salary income, net nonfarm and farm self-employment income, and other income, as specified below. In statistics on family income or household income, the combined incomes of all members of each family or household are treated as a single amount. For unrelated individual income and for income statistics of persons 14 years and over, the classification is by the amount of their own (individual) total income.

Income is tabulated by several intervals. For example, under $1,000, $1,000- $1,999... $9,000-$9,999, $10,000-$14,999, $15,000- $24,999, $25,000 and over. The 1960 census basic records included dollar amounts for each type of income in intervals of $10 from $1-$9 to $9,990-$9,999 and in intervals of $1,000 from $10,000-$10,999 to $24,000-$24,999. Two separate categories were provided for each of the following items: (1) no income and (2) incomes of $25,000 and over. (Net loss from self-employment and all other sources was included in intervals of $100 from $1 - $99 to $9,800-$9,899. Net losses of $9,900 and over were tabulated separately.)

In the 1970 census basic records, for dollar amounts of each type of income, questionnaire dollar entries within $100 intervals from $1-$99, $100-$199, to $99,900- !$99,999 are shown as one-tenth of the midpoint value for that interval. For example, any questionnaire entry between $100 and $199 is represented as 15 on the basic record; any questionnaire entry between $99,900 and $99,999 is represented as 9995 on the basic record. Similarly, dollar amounts within $10,000 intervals from $100,000-$109,999, $110,000-$119,999 to $980,000-$989,999 are shown as one-tenth of the midpoint value for that interval. For example, any questionnaire entry between $100,000 and $109,999 is represented as 10500 on the basic record; any questionnaire entry between $980,000 and $989,999 is represented as 98500 on the basic record. Separate categories are provided for no income and incomes of $990,000 or more. Net losses from self-employment income (section 104.12 below) and income from all other sources (section 104.23 below) are included in intervals of $100 from $1-$99 to $9,800-$9,899. Net losses of $9,900 or more are carried as one category.

Median and mean incomes are calculated for families, unrelated individuals, and persons 14 years and over for total income and for each type of income. (In the 1960 derivation of aggregate amounts for calculating mean income, persons in the open-ended interval $25,000 and over were assigned an estimated mean of $50,000 for each income type. In the 1970 derivation of aggregate amounts for each income type, persons in the open-ended interval $990,000 and over are assigned an estimated mean of $995,000.)

Earnings
The sum of wage or salary income and net self-employment income.

Wage or salary income
Money respondents reported receiving as wages, salary, commissions, bonuses, or tips from all jobs (before deductions for taxes, bonds, dues, etc.). Respondents were to include sick leave pay, but exclude military bonuses, reimbursements for business expenses, and pay in kind.

Self-employment income
Money respondents reported receiving as profits or fees (net income after business expenses) from their own business, professional practice, partnership, or farm. (If the enterprise lost money, respondents were to report the amount of loss. ) In 1970, self-employment income from a farm (including earnings as a tenant farmer or sharecropper, excluding payment in kind) was reported separately from other self-employment income.

Income other than earnings (other income)
Money respondents reported receiving from sources other than wages or salary and self-employment. In 1960, respondents were asked to report other income as a single amount. In 1970, respondents were asked to specify other income as follows.

Income from social security or railroad retirement
Includes U.S. Government payments to retired persons, to dependents of deceased insured workers, or to disabled workers; excludes Medicare reimbursements.

Income from public assistance or welfare
Includes amounts received from Federal, State, and local public programs such as aid for dependent children, old-age assistance, general assistance, and aid to the blind or totally disabled. Excludes separate payments for hospital or other medical care.

Income from all other sources
Includes interest; dividends; veterans payments of all kinds; retirement pensions from private employers, unions, and governmental agencies; and other regular payments such as net rental income, unemployment insurance benefits, workmens compensation, private welfare payments, alimony or child support, Armed Forces allotments and regular contributions from persons not members of the household. Excludes receipts from sale of personal property, capital gains, lump-sum insurance or inheritance payments, or payments in kind.

Poverty level
Not ascertained in 1960. In 1970, families and unrelated individuals (excluding college students in dormitories and Armed Forces personnel in barracks) are classified as being above or below the poverty level, using the poverty index adopted by a Federal Interagency Committee in 1969. This index takes into account such factors as family size, number of children, and farm-nonfarm residence, as well as the amount of money income. The poverty level is based on an economy food plan designed by the Department of Agriculture for emergency or temporary use when funds are low. The definition assumes that a family is classified as poor if its total money income amounts to less than approximately three times the cost of the economy food plan. These cutoff levels are updated every year to reflect changes in the Consumer Price Index.
In 1970, percent below poverty level is calculated as the proportion of the total universe which reports income below the poverty level: for example, below poverty level families as a percent of all families.

Income deficit
Not ascertained in 1960. In 1970, the income deficit is calculated as the difference between the total income of families and unrelated individuals and their respective poverty levels. Families and unrelated individuals can then be classified both by the absolute amount of their income deficit and by the ratio of their income to the poverty level. 1970 census tabulations express the income deficit in both absolute and relative terms.

Poverty areas
All census tracts and MCDS outside tracted areas will be classified as poverty or non-poverty areas on the basis of population census data. Poverty areas will be those tracts and MCDs with an incidence of poverty at least, one and one-quarter times the national average. 1970 is the first census for which such statistics will be a part of regular printed reports.