In determining the poverty status of families and unrelated individuals, the Census Bureau uses thresholds (income cutoffs) arranged in a two-dimensional matrix. The matrix consists of family size (from one person to nine or more people) cross-classified by presence and number of family members under 18 years old (from no children present to eight or more children present). Unrelated individuals and two-person families are further differentiated by age of reference person (RP) (under 65 years old and 65 years old and over).
To determine a person's poverty status, one compares the persons total family income in the last 12 months with the poverty threshold appropriate for that person's family size and composition (see example below). If the total income of that person's family is less than the threshold appropriate for that family, then the person is considered "below the poverty level," together with every member of his or her family. If a person is not living with anyone related by birth, marriage, or adoption, then the person's own income is compared with his or her poverty threshold. The total number of people below the poverty level is the sum of people in families and the number of unrelated individuals with incomes in the last 12 months below the poverty threshold.
Since ACS is a continuous survey, people respond throughout the year. Because the income questions specify a period covering the last 12 months, the appropriate poverty thresholds are determined by multiplying the base-year poverty thresholds (1982) by the average of the monthly inflation factors for the 12 months preceding the data collection. See the table below titled "Poverty Thresholds in 1982, by Size of Family and Number of Related Children Under 18 Years (Dollars)," for appropriate base thresholds. See the table "The 2007 Poverty Factors" for the appropriate adjustment based on interview month.
For example, consider a family of three with one child under 18 years of age, interviewed in July 2007 and reporting a total family income of $14,000 for the last 12 months (July 2006 to June 2007). The base year (1982) threshold for such a family is $7,765, while the average of the 12 inflation factors is 2.19359. Multiplying $7,765 by 2.19359 determines the appropriate poverty threshold for this family type, which is $17,033. Comparing the familys income of $14,000 with the poverty threshold shows that the family and all people in the family are considered to have been in poverty. The only difference for determining poverty status for unrelated individuals is that the person's individual total income is compared with the threshold rather than the familys income.
For example, consider a family of three with one child under 18 years of age, interviewed in July 2007 and reporting a total family income of $14,000 for the last 12 months (July 2006 to June 2007). The base year (1982) threshold for such a family is $7,765, while the average of the 12 inflation factors is 2.19359. Multiplying $7,765 by 2.19359 determines the appropriate poverty threshold for this family type, which is $17,033. Comparing the familys income of $14,000 with the poverty threshold shows that the family and all people in the family are considered to have been in poverty. The only difference for determining poverty status for unrelated individuals is that the person's individual total income is compared with the threshold rather than the familys income.
The 2007 Poverty Factors:
Interview Month |
Poverty Factors |
January |
2.14841 |
February |
2.15589 |
March |
2.16297 |
April |
2.17003 |
May |
2.17705 |
June |
2.18455 |
July |
2.19359 |
August |
2.20366 |
September |
2.21330 |
October |
2.22219 |
November |
2.22879 |
December |
2.23073 |
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 |