National poverty data are calculated using the official Census definition of poverty, which has remained fairly standard since it was introduced in the 1960s and is useful for measuring progress against poverty. Under this definition, poverty is determined by comparing pretax cash income with the poverty threshold, which adjusts for family size and composition. 1 In 2005, according to the official measure, 37 million people, 12.6 percent of the total U.S. population, lived in poverty (Table 1).

Is poverty different for different groups in the population?
The poverty rate represents an average over the entire population, and does not really tell us who, in particular, is well off, who is worse off. For that, it is necessary to examine poverty levels for particular groups. Most notably, blacks and Hispanics have poverty rates that greatly exceed the average. The poverty rate for all blacks and Hispanics remained near 30 percent during the 1980s and mid-1990s. Thereafter it began to fall. In 2000, the rate for blacks dropped to 22.1 percent and for Hispanics to 21.2 percent—the lowest rate for both groups since the United States began measuring poverty.

The Current Population Survey, from which the poverty statistics are drawn, implemented a new question in 2003 to collect information on race, allowing individuals to report one or more races. There is no way of knowing how people who reported more than one race would have reported their race under the old question. Table 1 shows that those who defined themselves as black only or as black and some other race had the highest poverty rates—around 25 percent. Among those of Hispanic origin, who can be of any race, the poverty rate was 21.8 percent. The poverty rate for Asians was 11.1 percent.

Among children under age 18, 17.6 percent, 13 million children, lived in poverty. (See Table 1 and also the FAQ, How Many Children Are Poor?) The poverty rate for those over 65, which in 1959 exceeded the overall poverty rate, fell below it beginning in 1982. In 2005, poverty rose slightly for this group—the rate was 10.1 percent. The poverty rate for whites who were not Hispanic was below the overall poverty rate from 1959 through 2003. In 2005 it was 8.3 percent.

In 2005, the poverty rate for families was 9.9 percent, comprising 7.7 million families. Of all family groups, poverty is highest among those headed by single women. In 2005, 28.7 percent of all female-headed families (4 million families) were poor, compared to 5.1 percent of married-couple families (2.9 million families).

Poverty levels also differ depending on where people live. The metropolitan poverty rate differs greatly between suburbs and the central city. In 1979, the average central city poverty rate was 15.7 percent; at its highest point, in 1993, it was 21.5; by 2005 it was 17.0 percent, almost twice the rate for the suburbs (9.3 percent). Poverty in rural areas is not negligible either; in 2005, 14.5 percent of people living outside metropolitan areas (that is, in the countryside and small country towns) were poor.

The poverty rate also varies by region and within regions. In 2005 it was greatest in the South, at 14.0 percent, and lowest in the Midwest and Northeast, at 11.3 percent, and between the two at 12.6 percent in the West. Adjoining states may have radically different levels of poverty. In 2005, the poverty rate in the state of Maryland was 9.7 percent—yet in the adjacent District of Columbia, it stood at 21.3 percent.

from

http://www.irp.wisc.edu/faqs/faq3.htm