	Introduction

Antipoverty interventions that provide resources to local communities, based on the characteristics of those communities, have been of interest to Congress. One such policy, dubbed the "10-20-30 provision," was implemented in the American Recovery and Reinvestment Act of 2009 (ARRA, P.L. 111-5 ). Title I, Section 105 of ARRA required the Secretary of Agriculture to allocate at least 10% of funds provided in that act from three rural development program accounts to persistent poverty counties; that is, to counties that have had poverty rates of 20% or more for the past 30 years, as measured by the 1980, 1990, and 2000 decennial censuses. One notable characteristic of this provision is that it did not increase spending for the rural development programs addressed in ARRA, but rather targeted existing funds differently. Motivation for Targeting Funds to Persistent Poverty Counties

Research has suggested that areas for which the poverty rate (the percentage of the population that is below poverty) reaches 20% experience systemic problems that are more acute than in lower-poverty areas. Therefore, policy interventions at the community level, and not only at the individual or family level, have been and may continue to be of interest to Congress. Data Sources Used in Identifying Persistent Poverty Counties

Poverty rates are computed using data from household surveys. Currently, the only data sources that provide poverty estimates for all U.S. counties are the American Community Survey (ACS) and the Small Area Income and Poverty Estimates program (SAIPE). Therefore, to determine whether an area is persistently poor in a time span that ends after 2000, it must first be decided whether ACS or SAIPE poverty estimates will be used for the later part of that time span. Reference Period of Estimate: SAIPE for One Year, ACS for a Five-Year Span

While the ACS has greater flexibility in the topics measured and the geographic areas provided, it can only provide estimates in five-year ranges for the smallest geographic areas. In the decennial census, ACS, and SAIPE estimates, poverty status also is not defined for persons living in college dormitories. Other interventions besides the 10-20-30 provision may be more appropriate for counties that have had a recent spike in the poverty rate. Poverty rates published by the Census Bureau are typically reported to one decimal place. Taking both the data source and the rounding method together, the list of persistent poverty counties could vary by roughly 70 to 100 counties in a given year depending on the method used. Before the mid-1990s, the only data source with a sample size large enough to provide meaningful estimates at the county level (and for other small geographic areas) was the decennial census.
Antipoverty interventions that provide resources to local communities, based on the characteristics of those communities, have been of interest to Congress. One such policy, dubbed the "10-20-30 provision," was implemented in the American Recovery and Reinvestment Act of 2009 (ARRA, P.L. 111-5). Title I, Section 105 of ARRA required the Secretary of Agriculture to allocate at least 10% of funds from three rural development program accounts to persistent poverty counties; that is, to counties that have had poverty rates of 20% or more for the past 30 years, as measured by the 1980, 1990, and 2000 decennial censuses. One notable characteristic of this provision is that it did not increase spending for the rural development programs addressed in ARRA, but rather targeted existing funds differently.
Research has suggested that areas for which the poverty rate (the percentage of the population that is below poverty) reaches 20% experience systemic problems that are more acute than in lower-poverty areas. Therefore, policy interventions at the community level (such as applying the 10-20-30 provision to other programs besides those cited in ARRA), and not only at the individual or family level, could continue to be of interest to Congress.
Poverty rates are computed using data from household surveys. The list of counties identified to be persistently poor may differ by roughly 70 to 100 counties in a particular year, depending on the surveys selected to compile the list and the rounding method used for the poverty rate estimates. Before the mid-1990s, the decennial census was the only source of county poverty estimates. However, currently, the only data sources that provide poverty estimates for all U.S. counties are the American Community Survey (ACS) and the Small Area Income and Poverty Estimates program (SAIPE). Therefore, to determine whether an area is "persistently" poor in a time span that ends after the year 2000, it must first be decided whether ACS or SAIPE poverty estimates will be used for the later part of that time span.
When determining the rounding method and data source to be used to compile a list of persistent poverty counties, the following may be relevant to consider:
Characteristics of interest: SAIPE is suited for poverty or median income alone; ACS for other topics in addition to poverty and income. Geographic areas of interest: SAIPE is recommended for counties and school districts only; ACS produces estimates for other small geographic areas as well. Reference period of estimate: SAIPE for one year; ACS for a five-year span. Rounding method for poverty rates: rounding to 20.0% (one decimal place) yields a shorter list than rounding to 20% (whole number).
Poverty status is not defined for all persons: foster children (unrelated individuals under age 15), institutionalized persons, and residents of college dormitories are excluded; the homeless are not targeted by household surveys; and areas with large numbers of students living off-campus may have high poverty rates.