Data Dictionary: ACS 2008 -- 2010 (3-Year Estimates)
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Data Source: U.S. Census Bureau
Table: B99011. Imputation Of Sex [3]
Universe: Total population
Table Details
B99011. Imputation Of Sex
Universe: Total population
Variable Label
B99011001
B99011002
B99011003
Relevant Documentation:
Excerpt from: Social Explorer; U.S. Census Bureau; American Community Survey 2008-2010 Summary File: Technical Documentation.
 
Imputation Rates
Missing data for a particular question or item is called item nonresponse. It occurs when a respondent fails to provide an answer to a required item. The ACS also considers invalid answers as item nonresponse. The Census Bureau uses imputation methods that either use rules to determine acceptable answers or use answers from similar housing units or people who provided the item information. One type of imputation, allocation, involves using statistical procedures, such as within-household or nearest neighbor matrices populated by donors, to impute for missing values.


Overall Person Characteristic Imputation Rate
This rate is calculated by adding together the weighted number of allocated items across a set of person characteristics, and dividing by the total weighted number of responses across the same set of characteristics.

Overall Housing Characteristic Imputation Rate
This rate is calculated by adding together the weighted number of allocated items across a set of household and housing unit characteristics, and dividing by the total weighted number of responses across the same set of characteristics.

These rates give an overall picture of the rate of item nonresponse for a geographic area.

Appendix A. Field of Degree Classification
Five-Group Classification Fifteen-Group Classification Examples
Science and Engineering Computers, Mathematics and Statistics Computer Science, Mathematics, General Statistics
Biological, Agricultural, and Environmental Sciences Cellular and Molecular Biology, Soil Sciences, Natural Resource Management
Physical and Related Sciences Physics, Organic chemistry, Astronomy
Psychology Psychology, Counseling, Child psychology
Social Sciences Criminology, Sociology, Political Science
Engineering Chemical Engineering, Thermal engineering, Electrical engineering
Multidisciplinary Studies Nutritional science, Cognitive science, Behavioral science
Science and Engineering Related Science and Engineering Related Pre-Med, Physical therapy, Mechanical engineering technology
Business Business Business administration, Accounting, Human resources development
Education Education Early childhood education, Higher education administration, Special education
Arts, Humanities, and Other Literature and Languages English, Foreign language and literature, Spanish
Liberal Arts and History Philosophy, Theology, American history
Visual and Performing Arts Interior design, Dance, Voice
Communications Mass communications, Journalism, Public relations
  Other Public Administration, Pre-law, Kinesiology


Four Main Group Classifications and Thirty-Nine Subgroup Classifications of Languages Spoken at Home with Illustrative Examples
Four Main Group Classifications Thirty-Nine Subgroup Classifications
Spanish Spanish or Spanish Creole Examples: Ladino, Pachuco
Other Indo-European languages French
  Examples: Cajun, Patois
  French Creole
  Examples: Haitian Creole
  Italian
  Portuguese or Portuguese Creole Examples: Papia Mentae
  German
  Example: Luxembourgian
  Yiddish
  Other West Germanic languages
  Examples: Dutch, Pennsylvania Dutch, Afrikaans
  Scandinavian languages
  Examples: Danish, Norwegian, Swedish
  Greek
  Russian
  Polish
  Serbo-Croatian
  Examples: Croatian, Serbian
  Other Slavic languages
  Examples: Czech, Slovak, Ukrainian
  Armenian
  Persian
  Gujarati
  Hindi
  Urdu
  Other Indic languages
  Examples: Bengali, Marathi, Punjabi, Romany
  Other Indo-European languages
  Examples: Albanian, Gaelic, Lithuanian, Romanian
Asian and Pacific Island languages Chinese
  Examples: Cantonese, Formosan, Mandarin
  Japanese
  Korean
  Mon-Khmer, Cambodian
  Hmong
  Thai
  Laotian
  Vietnamese
  Other Asian languages
  Examples: Dravidian languages (Malayalam, Telugu, Tamil), Turkish
  Tagalog
  Other Pacific Island languages
  Examples: Chamorro, Hawaiian, Ilocano, Indonesian, Samoan
All other languages Navajo
  Other Native North American languages
  Examples: Apache, Cherokee, Dakota, Pima, Yupik
  Hungarian
  Arabic
  Hebrew
  African languages
  Examples: Amharic, Ibo, Yoruba, Bantu, Swahili, Somali
  Other and unspecified languages
  Examples: Syriac, Finnish, Other languages of the Americas, not reported



Poverty Factors and Thresholds
The 2010 Poverty Factors:
Interview Month Poverty Factors
January 2.22296
February 2.22775
March 2.23167
April 2.23592
May 2.24004
June 2.24377
July 2.24574
August 2.24803
September 2.25017
October 2.25231
November 2.25449
December 2.25663


Poverty Thresholds in 1982, by Size of Family and Number of Related Children Under 18 Years Old (Dollars)
Size of family unit Related children under 18 years
  None One Two Three Four Five Six Seven Eight or more
One person (unrelated individual)                  
    Under 65 years 5,019                
    65 years and over 4,626                
Two persons                  
    Householder under 65 years 6,459 6,649              
    Householder 65 years and over 5,831 6,624              
Three persons 7,546 7,765 7,772            
Four persons 9,950 10,112 9,783 9,817          
Five persons 11,999 12,173 11,801 11,512 11,336        
Six persons 13,801 13,855 13,570 13,296 12,890 12,649      
Seven persons 15,879 15,979 15,637 15,399 14,955 14,437 13,869    
Eight persons or more 17,760 17,917 17,594 17,312 16,911 16,403 15,872 15,738  
Nine persons or more 21,364 21,468 21,183 20,943 20,549 20,008 19,517 19,397 18,649

Source: U.S. Census Bureau


Race Combination and Median Standard Distribution
Two or More Races (57 Possible Specified Combinations)
  1. White; Black or African American
  2. White; American Indian and Alaska Native
  3. White; Asian
  4. White; Native Hawaiian and Other Pacific Islander
  5. White; Some other race
  6. Black or African American; American Indian and Alaska Native
  7. Black or African American; Asian
  8. Black or African American; Native Hawaiian and Other Pacific Islander
  9. Black or African American; Some other race
  10. American Indian and Alaska Native; Asian
  11. American Indian and Alaska Native; Native Hawaiian and Other Pacific Islander
  12. American Indian and Alaska Native; Some other race
  13. Asian; Native Hawaiian and Other Pacific Islander
  14. Asian; Some other race
  15. Native Hawaiian and Other Pacific Islander; Some other race
  16. White; Black or African American; American Indian and Alaska Native
  17. White; Black or African American; Asian
  18. White; Black or African American; Native Hawaiian and Other Pacific Islander
  19. White; Black or African American; Some other race
  20. White; American Indian and Alaska Native; Asian
  21. White; American Indian and Alaska Native; Native Hawaiian and Other Pacific Islander
  22. White; American Indian and Alaska Native; Some other race
  23. White; Asian; Native Hawaiian and Other Pacific Islander
  24. White; Asian; Some other race
  25. White; Native Hawaiian and Other Pacific Islander; Some other race
  26. Black or African American; American Indian and Alaska Native; Asian
  27. Black or African American; American Indian and Alaska Native; Native Hawaiian and Other Pacific Islander
  28. Black or African American; American Indian and Alaska Native; Some other race
  29. Black or African American; Asian; Native Hawaiian and Other Pacific Islander
  30. Black or African American; Asian; Some other race
  31. Black or African American; Native Hawaiian and Other Pacific Islander; Some other race
  32. American Indian and Alaska Native; Asian; Native Hawaiian and Other Pacific Islander
  33. American Indian and Alaska Native; Asian; Some other race
  34. American Indian and Alaska Native; Native Hawaiian and Other Pacific Islander; Some other race
  35. Asian; Native Hawaiian and Other Pacific Islander; Some other race
  36. White; Black or African American; American Indian and Alaska Native; Asian
  37. White; Black or African American; American Indian and Alaska Native; Native Hawaiian and Other Pacific Islander
  38. White; Black or African American; American Indian and Alaska Native; Some other race
  39. White; Black or African American; Asian; Native Hawaiian and Other Pacific Islander
  40. White; Black or African American; Asian; Some other race
  41. White; Black or African American; Native Hawaiian and Other Pacific Islander; Some other race
  42. White; American Indian and Alaska Native; Asian; Native Hawaiian and Other Pacific Islander
  43. White; American Indian and Alaska Native; Asian; Some other race
  44. White; American Indian and Alaska Native; Native Hawaiian and Other Pacific Islander; Some other race
  45. White; Asian; Native Hawaiian and Other Pacific Islander; Some other race
  46. Black or African American; American Indian and Alaska Native; Asian; Native Hawaiian and Other Pacific Islander
  47. Black or African American; American Indian and Alaska Native; Asian; Some other race
  48. Black or African American; American Indian and Alaska Native; Native Hawaiian and Other Pacific Islander; Some other race
  49. Black or African American; Asian; Native Hawaiian and Other Pacific Islander; Some other race
  50. American Indian and Alaska Native; Asian; Native Hawaiian and Other Pacific Islander; Some other race
  51. White; Black or African American; American Indian and Alaska Native; Asian; Native Hawaiian and Other Pacific Islander
  52. White; Black or African American; American Indian and Alaska Native; Asian; Some other race
  53. White; Black or African American; American Indian and Alaska Native; Native Hawaiian and Other Pacific Islander; Some other race
  54. White; Black or African American; Asian; Native Hawaiian and Other Pacific Islander; Some other race
  55. White; American Indian and Alaska Native; Asian; Native Hawaiian and Other Pacific Islander; Some other race
  56. Black or African American; American Indian and Alaska Native; Asian; Native Hawaiian and Other Pacific Islander; Some other race
  57. White; Black or African American; American Indian and Alaska Native; Asian; Native Hawaiian and Other Pacific Islander; Some other race



Median Standard Distributions
In order to provide consistency in the values within and among data products, standard distributions from which medians and quartiles are calculated are used for the American Community Survey. Standard Distribution for Median Age:

[116 data cells]
Under 1 year
1 year
2 years
3 years
4 years
5 years
.
.
.
112 years
113 years
114 years
115 years and over
Standard Distribution for Median Age at First Marriage:
[9 cells]
5 to 9 years
10 to 14 years
15 to 19 years
20 to 24 years
25 to 29 years
30 to 34 years
35 to 39 years
40 to 44 years
45 to 49 years
Standard Distribution for Median Agricultural Crop Sales:
[5 data cells]
Less than $1,000
$1,000 to $2,499
$2,500 to $4,999
$5,000 to $9,999
$10,000 or more

Standard Distribution for Median Bedrooms:
[9 data cells]
No bedroom
1 bedroom
2 bedrooms
3 bedrooms
4 bedrooms
5 bedrooms
6 bedrooms
7 bedrooms
8 or more bedrooms
Standard Distribution for Median Condominium Fees:
[15 data cells]
Less than $50
$50 to $99
$100 to $199
$200 to $299
$300 to $399
$400 to $499
$500 to $599
$600 to $699
$700 to $799
$800 to $899
$900 to $999
$1,000 to $1,249
$1,250 to $1,499
$1,500 to $1,749
$1,750 or more
Standard Distribution for Median Contract Rent/Quartile Contract Rent/Rent Asked/Gross Rent:
[23 data cells]
Less than $100
$100 to $149
$150 to $199
$200 to $249
$250 to $299
$300 to $349
$350 to $399
$400 to $449
$450 to $499
$500 to $549
$550 to $599
$600 to $649
$650 to $699
$700 to $749
$750 to $799
$800 to $899
$900 to $999
$1,000 to $1,249
$1,250 to $1,499
$1,500 to $1,999
$2,000 to $2,499
$2,500 to $2,999
$3,000 or more
Standard Distribution for Duration of Current Marriage:
[101 data cells]
Under 1 year
1 year
2 years
3 years
4 years
5 years
.
.
.
97 years
98 years
99 years
100 years and over
Standard Distribution for Median Earnings and Median Income (Individuals):
[101 data cells]
Less than $2,500
$2,500 to $4,999
$5,000 to $7,499
$7,500 to $9,999
$10,000 to $12,499
$12,500 to $14,999
$15,000 to $17,499
$17,500 to $19,999
$20,000 to $22,499
$22,500 to $24,999
$500 to $549
$550 to $599
$600 to $649
$650 to $699
$700 to $749
$750 to $799
$800 to $899
$900 to $999
$1,000 to $1,249
$1,250 to $1,499
$1,500 to $1,999
$2,000 to $2,499
$2,500 to $2,999
$3,000 or more
Standard Distribution for Duration of Current Marriage:
[101 data cells]
Under 1 year
1 year
2 years
3 years
4 years
5 years
.
.
.
97 years
98 years
99 years
100 years and over
Standard Distribution for Median Earnings and Median Income (Individuals):
[101 data cells]
Less than $2,500
$2,500 to $4,999
$5,000 to $7,499
$7,500 to $9,999
$10,000 to $12,499
$12,500 to $14,999
$15,000 to $17,499
$17,500 to $19,999
$20,000 to $22,499
$22,500 to $24,999
$140,000 to $142,499
$142,500 to $144,999
$145,000 to $147,499
$147,500 to $149,999
$150,000 to $152,499
$152,500 to $154,999
$155,000 to $157,499
$157,500 to $159,999
$160,000 to $162,499
$162,500 to $164,999
$165,000 to $167,499
$167,500 to $169,999
$170,000 to $172,499
$172,500 to $174,999
$175,000 to $177,499
$177,500 to $179,999
$180,000 to $182,499
$182,500 to $184,999
$185,000 to $187,499
$187,500 to $189,999
$190,000 to $192,499
$192,500 to $194,999
$195,000 to $197,499
$197,500 to $199,999
$200,000 to $202,499
$202,500 to $204,999
$205,000 to $207,499
$207,500 to $209,999
$210,000 to $212,499
$212,500 to $214,999
$215,000 to $217,499
$217,500 to $219,999
$220,000 to $222,499
$222,500 to $224,999
$225,000 to $227,499
$227,500 to $229,999
$230,000 to $232,499
$232,500 to $234,999
$235,000 to $237,499
$237,500 to $239,999
$240,000 to $242,499
$242,500 to $244,999
$245,000 to $247,499
$247,500 to $249,999
$250,000 or more
$140,000 to $142,499
$142,500 to $144,999
$145,000 to $147,499
$147,500 to $149,999
$150,000 to $152,499
$152,500 to $154,999
$155,000 to $157,499
$157,500 to $159,999
$160,000 to $162,499
$162,500 to $164,999
$165,000 to $167,499
$167,500 to $169,999
$170,000 to $172,499
$172,500 to $174,999
$175,000 to $177,499
$177,500 to $179,999
$180,000 to $182,499
$182,500 to $184,999
$185,000 to $187,499
$187,500 to $189,999
$190,000 to $192,499
$192,500 to $194,999
$195,000 to $197,499
$197,500 to $199,999
$200,000 to $202,499
$202,500 to $204,999
$205,000 to $207,499
$207,500 to $209,999
$210,000 to $212,499
$212,500 to $214,999
$215,000 to $217,499
$217,500 to $219,999
$220,000 to $222,499
$222,500 to $224,999
$225,000 to $227,499
$227,500 to $229,999
$230,000 to $232,499
$232,500 to $234,999
$235,000 to $237,499
$237,500 to $239,999
$240,000 to $242,499
$242,500 to $244,999
$245,000 to $247,499
$247,500 to $249,999
$250,000 or more
$5,000 to $7,499
$7,500 to $9,999
$10,000 to $12,499
$12,500 to $14,999
$15,000 to $17,499
$17,500 to $19,999
$20,000 to $22,499
$22,500 to $24,999
$25,000 to $27,499
$27,500 to $29,999
$30,000 to $32,499
$32,500 to $34,999
$35,000 to $37,499
$37,500 to $39,999
$40,000 to $42,499
$42,500 to $44,999
$45,000 to $47,499
$47,500 to $49,999
$50,000 to $52,499
$52,500 to $54,999
$55,000 to $57,499
$57,500 to $59,999
$60,000 to $62,499
$62,500 to $64,999
$65,000 to $67,499
$67,500 to $69,999
$70,000 to $72,499
$72,500 to $74,999
$75,000 to $77,499
$77,500 to $79,999
$80,000 to $82,499
$82,500 to $84,999
$85,000 to $87,499
$87,500 to $89,999
$90,000 to $92,499
$92,500 to $94,999
$95,000 to $97,499
$97,500 to $99,999
$100,000 to $102,499
$102,500 to $104,999
$105,000 to $107,499
$107,500 to $109,999
$110,000 to $112,499
$112,500 to $114,999
$115,000 to $117,499
$117,500 to $119,999
$120,000 to $122,499
$122,500 to $124,999
$125,000 to $127,499
$127,500 to $129,999
$130,000 to $132,499
$132,500 to $134,999
$135,000 to $137,499
$137,500 to $139,999
$140,000 to $142,499
$142,500 to $144,999
$145,000 to $147,499
$147,500 to $149,999
$150,000 to $152,499
$152,500 to $154,999
$155,000 to $157,499
$157,500 to $159,999
$160,000 to $162,499
$162,500 to $164,999
$165,000 to $167,499
$167,500 to $169,999
$170,000 to $172,499
$172,500 to $174,999
$175,000 to $177,499
$177,500 to $179,999
$180,000 to $182,499
$182,500 to $184,999
$185,000 to $187,499
$187,500 to $189,999
$190,000 to $192,499
$192,500 to $194,999
$195,000 to $197,499
$197,500 to $199,999
$200,000 to $202,499
$202,500 to $204,999
$205,000 to $207,499
$207,500 to $209,999
$210,000 to $212,499
$212,500 to $214,999
$215,000 to $217,499
$217,500 to $219,999
$220,000 to $222,499
$222,500 to $224,999
$225,000 to $227,499
$227,500 to $229,999
$230,000 to $232,499
$232,500 to $234,999
$235,000 to $237,499
$237,500 to $239,999
$240,000 to $242,499
$242,500 to $244,999
$245,000 to $247,499
$247,500 to $249,999
$250,000 or more
Standard Distribution for Median Monthly Housing Costs:
[30 cells]
Less than $100
$100 to $149
$150 to $199
$200 to $249
$250 to $299
$300 to $349
$350 to $399
$400 to $449
$450 to $499
$500 to $549
$550 to $599
$600 to $649
$650 to $699
$700 to $749
$750 to $799
$800 to $899
$900 to $999
$1,000 to $1,249
$1,250 to $1,499
$1,500 to $1,749
$1,750 to $1,999
$2,000 to $2,499
$2,500 to $2,999
$3,000 to $3,499
$3,500 to $3,999
$4,000 to $4,499
$4,500 to $4,999
$5,000 to $5,499
$5,500 to $5,999
$6,000 or more
Standard Distribution for Median Real Estate Taxes Paid:
[14 data cells]
Less than $200
$200 to $299
$300 to $399
$400 to $599
$600 to $799
$800 to $999
$1,000 to $1,499
$1,500 to $1,999
$2,000 to $2,999
$3,000 to $3,999
$4,000 to $4,999
$5,000 to $7,499
$7,500 to $9,999
$10,000 or more
Standard Distribution for Median Rooms:
[14 data cells]
1 room
2 rooms
3 rooms
4 rooms
5 rooms
6 rooms
7 rooms
8 rooms
9 rooms
10 rooms
11 rooms
12 rooms
13 rooms
14 or more rooms
Standard Distribution for Median Selected Monthly Owner Costs/Median Selected Monthly Owner Costs by Mortgage Status (With a Mortgage):
[23 data cells]
Less than $100
$100 to $199
$200 to $299
$300 to $399
$400 to $499
$500 to $599
$600 to $699
$700 to $799
$800 to $899
$900 to $999
$1,000 to $1,249
$1,250 to $1,499
$1,500 to $1,749
$1,750 to $1,999
$2,000 to $2,499
$2,500 to $2,999
$3,000 to $3,499
$3,500 to $3,999
$4,000 to $4,499
$4,500 to $4,999
$5,000 to $5,499
$5,500 to $5,999
$6,000 or more
Standard Distribution for Median Selected Monthly Owner Costs by Mortgage Status (Without a Mortgage):
[17 data cells]
Less than $100
$100 to $149
$150 to $199
$200 to $249
$250 to $299
$300 to $349
$350 to $399
$400 to $499
$500 to $599
$600 to $699
$700 to $799
$800 to $899
$900 to $999
$1,000 to $1,249
$1,250 to $1,499
$1,500 to $1,999
$2,000 or more
Standard Distribution for Median Selected Monthly Owner Costs as a Percentage of Household Income by Mortgage Status:
[13 data cells]
Less than 10.0 percent
10.0 to 14.9 percent
15.0 to 19.9 percent
20.0 to 24.9 percent
25.0 to 29.9 percent
30.0 to 34.9 percent
35.0 to 39.9 percent
40.0 to 49.9 percent
50.0 to 59.9 percent
60.0 to 69.9 percent
70.0 to 79.9 percent
80.0 to 89.9 percent
90.0 percent or more
Standard Distribution for Median Total Mortgage Payment:
[21 data cells]
Less than $100
$100 to $199
$200 to $299
$300 to $399
$400 to $499
$500 to $599
$600 to $699
$700 to $799
$800 to $899
$900 to $999
$1,000 to $1,249
$1,250 to $1,499
$1,500 to $1,749
$1,750 to $1,999
$2,000 to $2,499
$2,500 to $2,999
$3,000 to $3,499
$3,500 to $3,999
$4,000 to $4,499
$4,500 to $4,999
$5,000 or more
Standard Distribution for Median Usual Hours Worked Per Week Worked in the Past 12 Months:
[9 data cells]
Usually worked 50 to 99 hours per week
Usually worked 45 to 49 hours per week
Usually worked 41 to 44 hours per week
Usually worked 40 hours per week
Usually worked 35 to 39 hours per week
Usually worked 30 to 34 hours per week
Usually worked 25 to 29 hours per week
Usually worked 15 to 24 hours per week
Usually worked 1 to 14 hours per week
Standard Distribution for Median Value/Quartile Value/Price Asked:
[24 data cells]
Less than $10,000
$10,000 to $14,999
$15,000 to $19,999
$20,000 to $24,999
$25,000 to $29,999
$30,000 to $34,999
$35,000 to $39,999
$40,000 to $49,999
$50,000 to $59,999
$60,000 to $69,999
$70,000 to $79,999
$80,000 to $89,999
$90,000 to $99,999
$100,000 to $124,999
$125,000 to $149,999
$150,000 to $174,999
$175,000 to $199,999
$200,000 to $249,999
$250,000 to $299,999
$300,000 to $399,999
$400,000 to $499,999
$500,000 to $749,999
$750,000 to $999,999
$1,000,000 or more
Standard Distribution for Median Vehicles Available:
[6 data cells]
No vehicle available
1 vehicle available
2 vehicles available
3 vehicles available
4 vehicles available
5 or more vehicles available
Standard Distribution for Median Year Householder Moved Into Unit:
[13 data cells]
Moved in 2010
Moved in 2009
Moved in 2008
Moved in 2007
Moved in 2006
Moved in 2005
Moved in 2004
Moved in 2003
Moved in 2002
Moved in 2001
Moved in 2000
Moved in 1990 to 1999
Moved in 1980 to 1989
Moved in 1970 to 1979
Moved in 1969 or earlier
Standard Distribution for Median Year Structure Built:
[16 data cells]
Built in 2010
Built in 2009
Built in 2008
Built in 2007
Built in 2006
Built in 2005
Built in 2004
Built in 2003
Built in 2002
Built in 2001
Built in 2000
Built 1990 to 1999
Built 1980 to 1989
Built 1970 to 1979
Built 1960 to 1969
Built 1950 to 1959
Built 1940 to 1949
Built 1939 or earlier



Excerpt from: Social Explorer; U.S. Census Bureau; American Community Survey 2008-2010 Summary File: Technical Documentation.
 
Sex
The data on sex were derived from answers to Question 3. Individuals were asked to mark either "male" or "female" to indicate their biological sex. For most cases in which sex was invalid, the appropriate entry was determined from other information provided for that person, such as the person's given (i.e., first) name and household relationship. Otherwise, sex was allocated from a hot deck.

Sex is asked for all persons in a household or group quarters. On the mailout/mailback paper questionnaire for households, sex is asked for all persons listed on the form. This form accommodates asking sex for up to 12 people listed as living or residing in the household for at least 2 months. If a respondent indicates that more people are listed as part of the total persons living in the household than the form can accommodate, or if any person included on the form is missing sex, then the household is eligible for Failed Edit Follow-up (FEFU). During FEFU operations, telephone center staffers call respondents to obtain missing data. This includes asking sex for any person in the household missing sex information. In Computer Assisted Telephone Interviews (CATI) and Computer Assisted Personal Interview (CAPI) instruments sex is asked for all persons. In 2006, the ACS began collecting data in group quarters (GQs). This included asking sex for persons living in a group quarters. For additional data collection methodology, please visit www.census.gov/acs.

Data on sex are used to determine the applicability of other questions for a particular individual and to classify other characteristics in tabulations. The sex data collected on the forms are aggregated and provide the number of males and females in the population. These data are needed to interpret most social and economic characteristics used to plan and analyze programs and policies. Data about sex are critical because so many federal programs must differentiate between males and females. The U.S. Departments of Education and Health and Human Services are required by statute to use these data to fund, implement, and evaluate various social and welfare programs, such as the Special Supplemental Food Program for Women, Infants, and Children (WIC) or the Low-Income Home Energy Assistance Program (LIHEAP). Laws to promote equal employment opportunity for women also require census data on sex. The U.S. Department of Veterans Affairs must use census data to develop its state projections of veterans' facilities and benefits. For more information on the use of sex data in Federal programs, please visit www.census.gov/acs.


Sex Ratio
The sex ratio represents the balance between the male and female populations. Ratios above 100 indicate a larger male population, and ratios below 100 indicate a larger female population. This measure is derived by dividing the total number of males by the total number of females and then multiplying by 100. It is rounded to the nearest tenth.

Question/Concept History
Sex has been asked of all persons living in a household since the 1996 ACS Test phase. When group quarters were included in the survey universe in 2006, sex was asked of all person in group quarters as well.
Beginning in 2008, the layout of the sex question response categories was changed to a horizontal side-by-side layout from a vertically stacked layout on the mail paper ACS questionnaire

Limitation of the data
Beginning in 2006, the population in group quarters (GQ) was included in the ACS. Some types of GQ populations have sex distributions that are very different from the household population. The inclusion of the GQ population could therefore have a noticeable impact on the sex distribution. This is particularly true for a given geographic area. This is particularly true for areas with a substantial GQ population.

The Census Bureau tested the changes introduced to the 2008 version of the sex question in the 2007 ACS Grid-Sequential Test (www.census.gov/acs/www/). The results of this testing show that the changes may introduce an inconsistency in the data produced for this question as observed from the years 2007 to 2008.

Comparability
Sex is generally comparable across different data sources and data years.

However, data users should still be aware of methodological differences that may exist between different data sources if they are comparing American Community Survey sex data to other data sources, such as Population Estimates or Decennial Census data. For example, the American Community Survey data are that of a respondent-based survey and subject to various quality measures, such as sampling and nonsampling error, response rates and item allocation. This differs in design and methodology from other data sources, such as Population Estimates, which is not a survey and involves computational methodology to derive intercensal estimates of the population. While ACS estimates are controlled to Population Estimates for sex at the nation, state and county levels of geography as part of the ACS weighting procedure, variation may exist in the sex structure of a population at lower levels of geography when comparing different time periods or comparing across time due to the absence of controls below the county geography level. For more information on American Community Survey data accuracy and weighting procedures, please see www.census.gov/acs/www/.

It should also be noted that although the American Community Survey (ACS) produces population, demographic and housing unit estimates, it is the Census Bureau's Population Estimates Program that produces and disseminates the official estimates of the population for the nation, states, counties, cities and towns and estimates of housing units for states and counties.