Measuring Poverty: A New Approach


Summary and Recommendations

The U.S. measure of poverty is an important social indicator that affects not only public perceptions of well-being in America, but also public policies and programs. The current measure was originally developed in the early 1960s as an indicator of the number and proportion of people with inadequate family incomes for needed consumption of food and other goods and services. At that time, the poverty "line" for a family of four had broad support. Since then, the poverty measure has been widely used for policy formation, program administration, analytical research, and general public understanding.

Like other important indicators, the poverty measure should be evaluated periodically to determine if it is still serving its intended purposes and whether it can be improved. This report of the Panel on Poverty and Family Assistance provides such an evaluation. Our major conclusion is that the current measure needs to be revised: it no longer provides an accurate picture of the differences in the extent of economic poverty among population groups or geographic areas of the country, nor an accurate picture of trends over time. The current measure has remained virtually unchanged over the past 30 years. Yet during that time, there have been marked changes in the nation's economy and society and in public policies that have affected families' economic well -being, which are not reflected in the measure. Improved data, methods, and research knowledge make it possible to improve the current poverty measure.

The panel proposes a new measure that will more accurately identify the poor population today. For example, for 1992, the year for which the panel had data available for analysis, the proposed measure, compared with the current measure, finds a lower poverty rate for people in families on public assistance and a higher poverty rate for people in working families. The differences are largely the result of two factors: first, the proposed measure counts not only cash assistance, but also the value of such in-kind benefits as food stamps; second, the proposed measure counts net earnings, after deductions for taxes and work expenses, instead of gross earnings. Equally important, the proposed measure will more accurately describe changes in the extent of poverty over time that result from new public policies and further social and economic change.

THE CURRENT POVERTY MEASURE: EVALUATION

The current poverty measure has a set of lines, or thresholds, that are compared with families' resources to determine whether or not they are poor. The thresholds differ by the number of adults and children in a family and, for some family types, by the age of the family head. The resources are families' annual before-tax money income.

The current thresholds were originally developed as the cost of a minimum diet times three to allow for expenditures on all other goods and services. The multiplier of three represented the after-tax money income of the average family in 1955 relative to the amount it spent on food. The central threshold for 1963 was about $3,100 for a family of four (two adults and two children). Because the thresholds have been adjusted only for estimated price changes, the 1992 threshold for a two-adult/two-child family of $14,228 repre sents the same purchasing power as the threshold of $3,100 did 30 years ago.

From the beginning, the poverty measure had weaknesses, and they have become more apparent and consequential because of far-reaching changes in the U.S. society and economy and in government policies.

  • First, because of the increased labor force participation of mothers, there are more working families who must pay for child care, but the current measure does not distinguish between the needs of families in which the parents do or do not work outside the home. More generally, the current measure does not distinguish between the needs of workers and nonworkers.

  • Second, because of differences in health status and insurance coverage, different population groups face significant variations in medical care costs, but the current measure does not take account of them.

  • Third, the thresholds are the same across the nation, although significant price variations across geographic areas exist for such needs as housing.

  • Fourth, the family size adjustments in the thresholds are anomalous in many respects, and changing demographic and family characteristics (such as the reduction in average family size) underscore the need to reassess the adjustments.

  • Fifth, more broadly, changes in the standard of living call into question the merits of continuing to use the values of the original thresholds updated only for inflation. Historical evidence suggests that poverty thresholds—including those developed according to "expert" notions of minimum needs—follow trends in overall consumption levels. Because of rising living standards in the United States, most approaches for developing poverty thresholds (including the original one) would produce higher thresholds today than the current ones.

  • Finally, because the current measure defines family resources as gross money income, it does not reflect the effects of important government policy initiatives that have significantly altered families' disposable income and, hence, their poverty status. Examples are the increase in the Social Security payroll tax, which reduces disposable income for workers, and the growth in the Food Stamp Program, which raises disposable income for beneficiaries. Moreover, the current poverty measure cannot reflect the effects of future policy initia tives that may have consequences for disposable income, such as changes in the financing of health care, further changes in tax policy, and efforts to move welfare recipients into the work force.

    The Panel on Poverty and Family Assistance concludes that the poverty measure should be revised to reflect more accurately the trends in poverty over time and the differences in poverty across population groups. Without revision, and in the face of continuing socioeconomic change as well as changes in government policies, the measure will become increasingly unable to inform the public or support research and policy making.

    It is not easy to specify an alternative measure. There are several poverty concepts, each with merits and limitations, and there is no scientific basis by which one concept can be indisputably preferred to another. Ultimately, to recommend a particular concept requires judgment as well as science.

    Our recommended changes are based on the best scientific evidence available, our best judgment, and three additional criteria. First, a poverty measure should be acceptable and understandable to the public. Second, a poverty measure should be statistically defensible. In this regard, the concepts underlying the thresholds and the definition of resources should be consistent. Third, a poverty measure should be feasible to implement with data that are available or can fairly readily be obtained.

    RECOMMENDATION: A NEW POVERTY MEASURE

    The official U.S. poverty thresholds should comprise a budget for the three basic categories of food, clothing, shelter (including utilities), and a small additional amount to allow for other needs (e.g., household supplies, personal care, non-work-related transportation). Actual expenditure data should be used to develop a threshold for a reference family of four—two adults and two children. Each year, that threshold should be updated to reflect changes in spending on food, clothing, and shelter over the previous 3 years and then adjusted for different family types and geographic areas of the country. The resources of a family or individual that are compared with the appropriate threshold to determine poverty status should be consistently defined to include money and near-money disposable income: that is, resources should include most in-kind benefits and exclude taxes and certain other nondiscretionary expenses (e.g., work expenses).

    The procedure for updating the poverty thresholds over time is an integral part of the proposed measure. Poverty measures tend to reflect their time and place. At issue is whether the thresholds ought to be updated for real changes in living standards only occasionally, or on a regular basis, and by how much. We propose a regular updating procedure to maintain the time series of poverty statistics. We also propose a conservative updating procedure that adjusts the thresholds for changes in consumption that are relevant to a poverty budget, rather than for changes in total consumption.

    We recommend that the proposed measure be adopted for official government use. We also urge the Statistical Policy Office in the U.S. Office of Management and Budget (which we presume will oversee the consideration and implementation of our recommendations) to establish a mechanism for regular review of the poverty measure on a 10-year cycle. No measure is without flaws, and it is important to have periodic reviews to identify improvements in concepts, methods, and data that may be needed. Altering a key social indicator is always difficult, but if a measure becomes markedly out of step with societal conditions, its utility as a barometer and guide to policy is greatly reduced.

    SETTING AND UPDATING THE POVERTY THRESHOLD

    We propose that the poverty-level budget for the reference family start with a dollar amount for the sum of three broad categories of basic goods and services food, clothing, and shelter (including utilities). The amount should be determined from actual Consumer Expenditure Survey (CEX) data as a percentage of median expenditures on food, clothing, and shelter by two-adult/ two-child families. This sum should then be increased by a modest additional amount to allow for other necessities. The allowance for "other expenses" is intended to cover such goods and services as personal care, household supplies, and non-work-related transportation. However, it does not include such nondiscretionary expenses as taxes and child care and other costs of working, which are treated as deductions from income (see below).

    Once a new reference family threshold is determined, it should be updated each year with more recent expenditure data. The recommended updating procedure will automatically, over time, reflect real changes in the consumption of basic goods and services without the need for a periodic and, inevitably, disruptive readjustment in the level. It represents a middle ground between the approach of simply updating the thresholds for price changes, which ignores changes in living standards over time, and the approach of updating the thresholds for changes in total consumption.

    As part of implementing the proposed poverty measure, the current official threshold should be reevaluated in light of the proposed threshold concept, which treats certain expenses as deductions from income rather than as elements of the poverty budget. That evaluation should also consider the real growth in the standard of living that has occurred since the current threshold was first set for 1963.

    We do not as a panel recommend a specific threshold with which to initiate the new poverty measure. Ultimately, that decision is a matter of judgment. We do, however, offer our conclusion about a range for that initial threshold. This conclusion represents our own judgment, informed by analysis of thresholds developed from other commonly used concepts, such as expert budgets, relative thresholds expressed as one-half median income or expenditures, and thresholds derived from responses to sample survey questions about the poverty line.

    We believe that a reasonable range for the initial threshold for the reference family of two adults and two children is $13,700 to $15,900 (in 1992 dollars). The lower number equals the expenditures for food, clothing, and shelter ($11,950) by families at the 30th percentile of all two-adult/two -children families, with a multiplier of 1.15 for other needed expenditures; the higher number equals the expenditures for food, clothing, and shelter ($12,720) by families at the 35th percentile of all two-adult/two-children families, with a multiplier of 1.25 for other needed expenditures.

    ADJUSTING THE THRESHOLD

    Given a poverty threshold for a reference family of two adults and two children, the next step is to develop appropriate thresholds for families with more and fewer members and different numbers of adults and children. We recommend that the reference family threshold be adjusted by means of an "equivalence scale" to determine thresholds for other family types. There is no consensus in the scientific literature on the precise form of an appropriate equivalence scale, although there is agreement on some properties of such a scale and that the scale implicit in the official poverty thresholds is flawed.

    We recommend that the scale recognize that children under age 18 on average consume less than adults, but that the scale not further distinguish family members by age or other characteristics. We also recommend that the scale add a decreasing amount for each adult (or adult equivalent) family member to reflect economies of scale available to larger families, such as their ability to buy food and other items in bulk and jointly use many durable goods.

    Evidence of cost-of-living differences among geographic areas—such as between metropolitan and nonmetropolitan areas—suggests that the poverty thresholds should be adjusted accordingly, but inadequate data make it difficult to determine appropriate adjustments. As a first and partial step, we recom mend that the housing component of the poverty thresholds be indexed to reflect variations in housing costs across the country. This adjustment can be made by analyzing decennial census data with the methodology developed by the U.S. Department of Housing and Urban Development (HUD) to estimate rents for comparable apartments in different localities. We believe the available data support reasonable adjustments for several population size groups of metropolitan areas within each of nine regions of the country. The resulting geographic index should be applied to the housing component of the thresholds. It may also be possible to update the index values each year (rather than at 10-year intervals) by applying the updating methods used by HUD.

    We do not recommend adjustments for other budget items at this time because good data for such adjustments are lacking and because the available research suggests that variations in the costs of other budget items are not large. However, more research would be very helpful to develop refined methods and data by which to adjust the poverty thresholds more accurately for geographic cost-of-living differences for housing and other goods and services. One source of improved data could be the area price index program of the Bureau of Labor Statistics (BLS).

    DEFINING FAMILY RESOURCES

    It is important that family resources are defined consistently with the threshold concept in any poverty measure. The current measure violates this principle, as has some recent work to investigate alternatives. Examples are measures that add the value of public and private health insurance benefits to families' resources without adjusting the thresholds to account for medical care needs. Such measures should be discontinued.

    For consistency, we recommend that family resources be defined as money and near-money disposable income. More precisely, the definition should include money income from all sources, as well as the value of such in-kind benefits as food stamps and public housing. It should exclude out-of-pocket medical care expenditures, including health insurance premiums; income and payroll taxes; child care and other work-related expenses; and child support payments to another household. The child care deduction should be capped and apply only to families in which there is no adult at home to provide the care; the deduction for other work expenses should be a flat amount per week worked.

    We believe there is widespread agreement among researchers about the appropriateness of such adjustments to income as deducting taxes and work expenses, which are a cost of earning income and cannot be used for consumption, and about adding the value of in-kind benefits that support consumption. The only important area of disagreement concerns medical care benefits.

    Trying to account for private and public medical insurance benefits—important as they clearly are—in the same way as in-kind benefits for such items as food and housing would greatly complicate the poverty measure and cloud its interpretation. A chief reason is the wide variation in health care needs among the population: Some people have high medical costs; some have none. Hence, the proposed poverty measure does not include an allowance for medical expenses, either those that might be covered by insurance or paid for out of pocket; for consistency, the proposed resource definition does not add the value of health insurance. Also for consistency, the proposed definition subtracts out-of-pocket medical care expenses from income: even with insurance, many people must pay out of pocket to obtain that insurance or to receive care, and such expenses reduce disposable income.

    Although the proposed poverty measure excludes medical care from both the thresholds and resources, it will reflect changes in health care policy that affect disposable income. For example, if changes in health care financing reduce out-of-pocket medical expenditures and thereby free up resources for food, housing, and other consumption, the proposed measure will show a lower poverty rate; the current measure would not show this effect. We also recommend that appropriate agencies develop direct indicators of the extent to which families lack or have inadequate health insurance that puts them at risk of not being able to afford needed treatment. These "medical care risk" measures should be cross-tabulated with but kept separate from the economic poverty measure.

    EFFECTS

    To consider the effects of our proposed measure, we estimated poverty rates under both the current and the proposed measures with data from the March 1993 Current Population Survey (CPS), supplemented with data from the Survey of Income and Program Participation (SIPP) and other sources.

    In one set of comparisons, we kept the overall poverty rate the same for both measures—14.5 percent in 1992. The results show important distributional effects on the makeup of the poverty population under the proposed measure: most strikingly, higher poverty rates for families with one or more workers and for families that lack health insurance coverage and lower rates for families that receive public assistance. The results also show higher poverty rates in the Northeast and West and lower rates in the South and, to a lesser extent, in the Midwest.

    In another set of comparisons, we used the midpoint of our suggested range for the two-adult/two-child family threshold—14,800. With this threshold, a scale economy factor of 0.75, and the other features of our measure, the poverty rate increased from 14.5 percent to 18.1 percent; with a scale economy factor of 0.65, the poverty rate increased to 19.0 percent. The changes in the resource definition increased the rate more than the changes in the thresholds. If we had been able to use SIPP data exclusively, we estimate that the rate would have increased less, from 14.5 percent to 15 or 16 percent (depending on the scale economy factor), because SIPP obtains more complete income reporting for lower income people than does the March CPS.

    NEEDED DATA

    Full and accurate implementation of the proposed poverty measure will require changes and improvements in data sources. We recommend that SIPP become the source of official poverty statistics in place of the March CPS. SIPP asks more relevant questions than the March CPS and obtains income data of higher quality. Also, because SIPP is an income survey rather than a supplement to a labor force survey, it is better able to satisfy the data require ments for an improved measure of poverty, both now and in the future.

    Because analysis with other surveys (including the March CPS) and with the decennial census often requires indicators of poverty status, we encourage research on the estimation of disposable income from these data sources. Finally, with regard to expenditure data, we support a review of the Consumer Expenditure Survey to identify changes, especially larger sample sizes, that would improve its usefulness for poverty measurement and other impor tant analyses of consumption, income, and savings.

    OTHER ISSUES IN POVERTY MEASUREMENT

    RELATING THE POVERTY MEASURE TO ASSISTANCE PROGRAMS

    More than 25 government programs that provided benefits and services to low-income families in 1994—such as food stamps, Head Start, Legal Services, Medicaid—linked their need standard for determining eligibility for some or all applicants to the U.S. Department of Health and Human Services poverty guidelines, which are derived from the official poverty thresholds. The use of the proposed measure would improve the targeting of benefits to needy families, and we encourage program agencies to consider adopting it as an eligibility criterion in place of the current measure. In doing so, program agencies should consider whether the proposed measure may need to be modified to better serve program objectives. For example, the proposed definition of family resources may add administrative burdens in programs that currently obtain crude measures of applicants' gross money income to assess eligibility because more information is needed to determine applicants' disposable income. In these instances, it may be preferable to implement a less detailed definition.

    Program agencies should also consider the implications of the recommended method for updating the poverty thresholds. There may be consequences for program caseloads or waiting lines and costs if, overtime, thresholds developed under that method rise at a faster rate than thresholds that are simply adjusted for inflation. With constrained budgets, the relationship of program need standards to the poverty thresholds may need periodic adjustment.

    In the Aid to Families with Dependent Children (AFDC) program, for which we were asked to consider issues of a national minimum benefit standard, federal law currently defines "countable income." The definition is similar in concept, if not in specifics, to the proposed disposable income definition of family resources. However, a unique feature of AFDC is that the states establish need standards for eligibility but are allowed to and often do pay benefits below that standard. Most state need standards and, even more so, most state benefit standards are considerably below the poverty thresholds, and the level varies widely across states—more widely than can be explained by differences in living costs.

    Currently, more than a dozen states link their need standard in some way to the current poverty guidelines. Again, the proposed measure would be an improvement for this purpose. We encourage the states to consider the use of the proposed measure, which includes an adjustment to the thresholds for geographic differences in housing costs, in setting their need standard for AFDC.

    It would also seem reasonable to consider the thresholds that are developed under the proposed measure as a goal or benchmark in any debate about state or federal AFDC benefit standards. However, many factors properly enter into a determination of program benefit levels, and the result may well be standards that differ from those that make sense for a statistical measure of poverty. Such factors include constraints on available funding, the desire to target benefits to particular population groups, interactions among programs, and the desire to provide incentives to participants and potential participants, such as incentives to prefer work over welfare. Ultimately, the determination of appropriate assistance program benefit standards involves political judg ments about the appropriate balance of competing program objectives within the constraints of scarce resources. We hope, by reviewing the issues, to help clarify the policy debate.


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