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Using the Consumer Expenditure Surveyto Teach Poverty MeasurementAmy McCormick Diduch aa Mary Baldwin CollegePublished online: 18 Jan 2012.

To cite this article: Amy McCormick Diduch (2012) Using the Consumer Expenditure Surveyto Teach Poverty Measurement, The Journal of Economic Education, 43:1, 99-106, DOI:10.1080/00220485.2012.636714

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THE JOURNAL OF ECONOMIC EDUCATION, 43(1), 99–106, 2012Copyright C© Taylor & Francis Group, LLCISSN: 0022-0485 print/2152-4068 onlineDOI: 10.1080/00220485.2012.636714

ECONOMIC INSTRUCTION

Using the Consumer Expenditure Surveyto Teach Poverty Measurement

Amy McCormick Diduch

Poverty measurement is often controversial, but good public policy relies crucially on a broadlysupported and understood poverty measure. In 2010, the U.S. Census Bureau announced it would beginregular reporting of a new supplemental poverty measure in October 2011. The present article providesbackground information for a student exercise (available, on request, from the author) on alternativepoverty measurement techniques. The exercise allows students to use current data from the ConsumerExpenditure Survey (available through the Bureau of Labor Statistics at http://www.bls.gov/cex/; U.S.Department of Labor 2010) and other sources to calculate and compare several absolute and relativepoverty thresholds. The exercise invites students to draw their own conclusions about the pros andcons of different measures, including the new supplemental measure. Data sources are easily updatedas new information becomes available.

Keywords active learning, Consumer Expenditure Survey, poverty measurement

JEL codes A22, I32

Poverty measurement is controversial, political, difficult, and important. Measures of povertyresist consensus in part because people disagree about their purpose: To determine who qualifiesfor government benefits? To establish the number of people whose consumption falls below socialstandards? To track those who do not have access to the barest necessities? To enumerate those whodo not have the means to function at socially acceptable levels? To decide whether governmentprograms effectively pull families out of poverty? Should we focus on income, consumption,or well-being? The only area of agreement is that the current U.S. poverty threshold does notadequately accomplish any of these goals.

The debate over appropriate methods for measuring poverty includes many technical details:equivalence scales, imputations of income, and geographical adjustments. It includes disagree-ments about what counts as income and what to include as necessities. However, in searchingfor a single yardstick, we likely miss the greater point that no one tool can answer all of our

Amy McCormick Diduch is a professor of economics at Mary Baldwin College (e-mail: adiduch@mbc.edu).

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questions about poverty. Moreover, every attempt to measure poverty is inherently subjective.Thus, poverty measurement should be a great subject for classroom debate. Furthermore, byannouncing its intentions of implementing a new supplemental poverty measure in 2011, theCensus Bureau has made this debate particularly timely and relevant for student attention.

This article provides a review of the concepts and decisions necessary for the creation of povertythresholds (which are used to count the number of people whose economic well-being falls belowa given standard) and describes an exercise that allows students to calculate, compare, and debatethese thresholds. The student exercise is based on easily obtainable data from the ConsumerExpenditure Survey (CEX; U.S. Department of Labor 2010; available through the Bureau ofLabor Statistics at http://www.bls.gov/cex/), the U.S. Census Bureau, the U.S. Department ofAgriculture (USDA), and the U.S. Department of Housing and Urban Development (HUD), andis available on request from the author.

DEVELOPING POVERTY THRESHOLDS: THEORY AND PRACTICE

Absolute poverty is defined with reference to the minimum sufficient resources needed to purchasean acceptable level of consumption. A pure absolute threshold is created by listing necessarypurchases and determining the cost of these items. Those individuals or families who lackthe economic resources to purchase this “basket” of goods—known as a standard budget—areconsidered to be poor. Absolute poverty thresholds are closely aligned with what many peopleconsider to be poverty and can lead to straightforward policy prescriptions and evaluations ofpolicy effectiveness.

Many of the earliest attempts to define and describe poverty in the United States were preparedby social workers (through their work with charities and settlement houses) in the late 19th andearly 20th centuries (Fisher 1997b). Most of these early studies were built around standardbudgets, including measures of minimally adequate food and housing. Researchers typicallymade a distinction between a minimum adequate standard of living (and the fair or living wagesnecessary to attain this modest level of comfort) and inadequate standards of living, described assubsistence, charity, or poverty levels that are not sustainable for the long term. Early researchersrecognized the need to vary living standards categories by geography (urban vs. rural, north vs.south) and by family size.

Disagreements about the appropriate composition of the standard budget and the measurementof minimally adequate consumption have existed ever since the first budgets were proposed.Wilbur Atwater, an American nutrition scientist, argued in the 1880s that American workers, inspending 50 percent of their incomes on food, were extravagant in their food-buying habits (andthus their pleas for higher wages were unjustified). Atwater felt that fruits and vegetables werewasteful extravagances and recommended a diet maximizing calories and protein relative to cost.Although Atwater’s prescriptions were revised after vitamins and minerals were discovered, hismethodology for finding the most “efficient” diet influenced many of the minimum-cost foodbudgets developed in the early 20th century over the objections of many who viewed the foodallowance to be impossibly low (Fisher 1997b).

Such disagreements point to the main objection to the use of standard budgets: It is difficult tofind agreement on the components of the basket of necessities (Electricity? Sure. A cell phone?Maybe. A computer? Not sure). Furthermore, there is no generally accepted definition of minimum

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adequate consumption beyond food (and perhaps housing). Finally, the socially accepted valueof an absolute poverty threshold will increase over time as overall living standards increase,requiring the “market basket” used in the standard budget to be revised over time. (For interestedinstructors and students who want to try building a standard budget, the Economic Policy Institute(2008) provides a “Family Budget Calculator” at http://www.epi.org/content/budget calculator/.)

Relative poverty measures are explicitly tied to the standards of living for a community asa whole. Arguing in favor of a relative poverty line calculated at 50 percent of median familyincome, Victor Fuchs wrote, “[I]t seems to me that there are some powerful economic, politicaland ethical arguments in favor of sharply reducing the number of Americans whose income isso far below the average that they are effectively out of the mainstream of American life” (1967,92). Relative poverty thresholds appeal to those who believe that large income inequalities implylarge inequalities in the distribution of opportunities.

Relative poverty lines are frequently used to facilitate cross-national comparisons of poverty(Smeeding 2006). While researchers have frequently used Fuchs’ suggestion of 50 percent ofmedian income, the United Kingdom and other European Union countries currently report povertythresholds calculated from 60 percent of median income (adjusted for family size and comparabledefinitions of income).

Discussion of relative poverty thresholds centers around two main concerns: (1) whetherrelative poverty is indistinguishable from income inequality; and (2) whether it adequately reflectstrue changes in well-being when average incomes are rising or falling. It is true that when incomesrise throughout the income distribution, measured poverty rates may not change at all, even thoughthe absolute well-being of families is clearly increasing. Similarly, when incomes throughout thedistribution are falling, measured poverty rates may not reflect any increase in deprivation.However, a relative poverty threshold is not synonymous with income inequality: If incomesincrease for the rich but no one else, median income does not change and neither does the povertythreshold.

Hybrid poverty thresholds combine aspects of absolute and relative poverty measurement.In general, this type of poverty threshold is tied to the consumption of one or more necessities(following the absolute approach), but the adequate consumption level is derived from actualconsumption patterns of the population (following the relative approach). These “relatively ab-solute” thresholds then use a multiplier-based adjustment to account for consumption of otheritems.

The official U.S. poverty threshold is often described as an “absolute” threshold, but it wasoriginally anchored to the food-spending patterns (for food prepared at home and also food eatenaway from home) of the average household in 1955. Mollie Orshansky’s intent (as described byFisher, 1997a) was to measure the distribution of economic opportunities and how they variedby demographic groups. Orshansky imagined how an average household, which spent 1/3 of itsincome on food, would adjust to a reduction in family income. She made the assumption that theproportion of income spent on food would remain constant as the family reduced expenditures;thus the cost of a minimally adequate food budget, multiplied by 3, would draw a line belowwhich a family could not thrive for a sustained length of time. Orshansky calculated necessaryfood expenditures for nonfarm and farm families of different sizes and structures at two differentUSDA food budget levels: the economy level and the low-cost level. Like the researchers whocame before her, Orshansky thought that the economy-level food budget was too meager forthe long term and favored the use of the low-cost food budget for setting poverty thresholds.

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However, the official U.S. poverty threshold adopted in 1969 used the economy food budgets andsimplified Orshansky’s family categories.

Similar reasoning can be used to create a poverty threshold based on a housing multiplier.Although Patricia Ruggles argues in favor of an expert-determined “standard budget” povertythreshold, updated each decade, she presents two consumption-based poverty thresholds—anupdated food multiplier threshold and a housing standard threshold—in her 1990 book, Drawingthe Line. She bases her housing consumption threshold on standards established by the Section8 Subsidized Housing Program, which reports data on Fair Market Rents and sets the maximumproportion of income that tenants can be required to pay for housing costs (currently 30 percent).Using the national average value for Fair Market Rent, Ruggles calculates the implied minimumincome threshold by dividing annual rent by 0.30 (equivalent to using a multiplier of 1/0.30=3.33).

In 1995, the National Statistics Committee of the National Academies of Science (NAS) (Citroand Michael 1995) recommended a new poverty threshold that applies the multiplier approach toexpenditures on food, shelter, and clothing for households at the 30th or 35th income percentile.This expenditure level, measured using the CEX, is adjusted by a multiplier of 1.15 or 1.25 toallow for consumption of personal items and other necessities. Moreover, the NAS thresholdmakes significant changes to the measurement of a family’s economic resources. Work-relatedexpenses and out-of-pocket medical expenses are subtracted from disposable income to determinewhether a household falls below the poverty threshold (Citro and Michael 1995). Since 1995,many poverty measurement researchers have praised the NAS approach and advocated for its use.Unlike the current U.S. threshold, the NAS measure adjusts to changes in tax policy and in-kindbenefits; it also reflects changes in work behavior and health care expenses that can significantlyreflect family well-being (Blank and Greenberg 2008).

In the spring of 2010, the Census Bureau (U.S. Census Bureau 2010) announced that it wouldbegin reporting a new supplemental poverty measure based on the NAS recommendations byfall of 2011 (assuming U.S. congressional approval of funding). The new experimental thresholdis based on food, clothing, shelter, and utilities (FCSU) expenditure data from the CEX, times1.2 to cover other expenses, for families with two children at the 33rd percentile of the expen-diture distribution. The threshold is adjusted for geographical differences in housing costs andfamily structure (including adjustments that consider cohabiting couples as family units) andcompared to a comprehensive measure of family resources that includes government transferssuch as nutritional assistance, subsidized housing, energy assistance, and the Earned Income TaxCredit. Out-of-pocket medical expenses, work expenses, child care, child support, and taxes aresubtracted from family resources. While the current official poverty threshold will remain thestandard for government benefit determination, the supplemental measure will likely providebetter information about the extent to which government benefit programs lift families out ofpoverty thanks to its improved measurement of family resources.

The proposed supplemental poverty measure does change our notion of who is poor. Under thesupplemental measure, the elderly appear to suffer substantially more economic hardship (largelydue to high out-of-pocket medical expenses). Measured poverty rates are also noticeably higher formarried-couple families and male-householder families. The largest decline in measured povertyrates comes for the new family unit measure based on cohabitation. Under this new “family unit”designation, all individuals residing under one roof are considered a “family unit” for purposes ofpoverty measurement, under the assumption that roommates and cohabiting couples benefit fromeconomies of scale that may result in overmeasurement of poverty under the official measure.

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The poverty threshold is higher under the supplemental measure ($24,869 in 2008, comparedto $21,834 for a two-parent, two-child family under the official measure), but the new familyresource measure is more comprehensive (Short 2010).

The primary criticism of the new measure is that it veers too far toward a “relative” standard ofpoverty: As incomes grow, consumption also grows, and the poverty threshold can move fartheraway from enumerating the barest necessities (Rector 2010). However, because the supplementalmeasure is based on consumption of necessities, not income, it is likely that expenditures in thiscategory will increase more slowly than income. As a result, poverty rates will not necessarilyincrease (or increase much) solely because median income increases.

POVERTY THRESHOLD STUDENT EXERCISE: USES AND LIMITATIONS

I developed the in-class exercise described below to give students in an introductory, inter-disciplinary course on poverty and inequality an opportunity to calculate and compare severalalternative poverty thresholds, including one that closely corresponds to the new supplementalpoverty measure. The exercise takes approximately 30–40 minutes of class time to complete ifstudents work in groups. At least one student in each group needs a calculator (although thecalculations themselves are uncomplicated). Discussion takes another 20–30 minutes. The exer-cise also works as a take-home assignment that can be discussed in class. Prior to completingthis exercise, students have been introduced to the concepts of absolute, relative, and subjectivepoverty and have learned how the U.S. poverty threshold was initially calculated.

The exercise is based on data from the 2009 CEX (U.S. Department of Labor 2010). Althoughthe CEX was not designed specifically for poverty research, it has received attention in recentyears because it is the one national (and annual) survey that includes income and detailedexpenditure data, providing researchers with an unequaled opportunity to compare the adequacyof consumption to a household’s access to economic resources. (By comparison, the Panel Studyof Income Dynamics (PSID) (housed at the University of Michigan, Institute for Social Research)provides superior income data but only records expenditures on housing and food). The CEXsurveys approximately 5,000 households per quarter and provides data on market income as wellas transfer payments and taxes. The survey records expenditures in numerous detailed categories.One should be mindful of a few disadvantages to the CEX: Unlike the PSID, the CEX doesnot oversample low-income households, and the sample size is smaller. Concerns about missingincome data have been addressed through the imputation of income. (Instructors might askstudents to explore the CEX website at http://www.bls.gov/cex/ prior to completing the exercise.)

Additional data are from the U.S. Department of Agriculture (on the cost of food plans),the U.S. Department of Housing and Urban Development (on the fair market rental rates fortwo bedroom apartments), and the Census Bureau (on income at selected percentiles). All ofthis can be updated easily over time by the instructor (or by students themselves). To facilitatecomparisons across different types of poverty thresholds, I needed to choose a “reference family.”According to the Census Bureau, the average household in 2009 contained 2.59 people; I havechosen a one-adult, two-child family for use in the student exercise. Given that my referencefamily is slightly larger than the average household size, calculations based on average householdconsumption or income could slightly underestimate the amount of resources this three-personfamily will need.

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The exercise begins with calculations of relative poverty thresholds. At 50 percent of medianincome, the poverty threshold would be set at $24,889, considerably higher than the 2009 officialpoverty threshold of $17,098 for a family of three. Students are asked to think about how relativepoverty thresholds change when all incomes are rising or falling and how they change whenincomes at the top are rising while others remain constant.

Before calculating the hybrid poverty thresholds, students are asked to look at expenditurepatterns and incomes reported in the CEX. Their attention is drawn to the fact that consumersat the bottom of the income distribution report expenditure levels that exceed income. The CEXhas been adjusted over time to account for possible income underreporting; consequently, thereported difference between income and expenditure mostly indicates households drawing onsavings, borrowing from relatives, or taking out loans.

To calculate the updated food multiplier poverty threshold, I ask students to think aboutwhether the thrifty plan or the low cost plan should be used. Orshansky (Fisher 1997a) used bothto create two separate sets of thresholds, but the official U.S. poverty line used the thrifty plan.Since Orshansky based her multiplier on the total food expenditures of the average household, Idirect students to do the same. The average household in the middle of the income distributionspends 13.3 percent of its income on food. The food budget multiplier is 1/0.133 or 7.52. The“thrifty plan” budget for a three-person family is $415 per month or $4,980 per year. Usingthe food budget multiplier, the implied (annual) poverty threshold is $4,980 × 7.52 = $37,450.The student handout explains why this method produces a significantly higher poverty threshold.Instructors may want to anticipate questions about the relationship between poverty and obesitythat could arise during this section.

Although Ruggles (1990) used the Department of Housing and Urban Development’s guidelineof 30 percent of income in developing her housing budget poverty thresholds, I have directedstudents to use actual housing expenditures by the average consumer unit (to be consistent withthe methodology used for calculating the food budget threshold). In 2009, the average householdin the middle 20 percent of the income distribution spent 36 percent of its income on housing,implying a housing budget multiplier of 1/0.36 = 2.78. To get a national poverty threshold,students use the national average for Fair Market Rent of $889 per month (or $10,668 per year).The housing budget poverty threshold for a family of three would be $10,668 × 2.78 = $29,657.The student handout provides a table of Fair Market Rents for selected cities and counties inVirginia that makes clear that housing costs vary significantly by geographical location.

The FCSU poverty threshold is calculated by summing expenditures on food, apparel, shelter,and utilities for the household in the second lowest quintile. Students should be careful whenlooking for the appropriate subcategories of expenditures: Note that “shelter” is a subcategory of“housing.” The average household in the second lowest quintile spent $4,569 on food; $6,807 onshelter; $3,069 on utilities; and $1,161 on apparel in 2009. Adding these and multiplying by 1.2gives us a poverty threshold of $18,727.

To facilitate comparisons among the different poverty thresholds, I make it clear that we needto measure a family’s income consistently and carefully. I explain how this is done by using thenew supplemental measure and ask students to consider whether our hypothetical family withan adjusted income of $20,000 per year is poor. Class discussion begins with their thresholdresults and the pros and cons of each approach. Does the measure reflect an accepted degreeof economic hardship? Is it likely to provide consistent estimates over time? Is it reasonablyeasy to calculate and understand? Does it adequately reflect a family’s well-being? Through

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the process of calculating the alternatives, students appreciate the value of looking at povertythrough different lenses. As a result, students become interested in looking for other ways ofmeasuring well-being or hardship. This can lead to a fruitful discussion of capabilities ap-proaches to poverty measurement or consideration of data on food security and other hardshipmeasures.

What is missing from this simplification? First, the exercise focuses solely on setting anappropriate poverty threshold. It does not discuss other complementary methods of assessingwell-being, including measures of the “poverty gap” (the distance between a family’s resourcesand the poverty threshold) or measures of poverty duration. Second, the exercise does not provideenough of the details necessary to calculate or fully discuss appropriate measures of a family’savailable economic resources. Clearly, this step is critical to our understanding of whether afamily’s economic status is unacceptable, and instructors are encouraged to follow this exercisewith discussion of how to measure economic resources. Short (2010) provides a reasonablyaccessible overview of how resources are measured for the new supplemental poverty threshold.Third, the exercise leaves out the technical details of the creation and use of equivalence scales.Such scales are necessary to adjust poverty thresholds for different family sizes/types (andpotentially for geographic variations in housing costs). Careful consideration has been givento the creation of appropriate equivalence scales for the newly proposed supplemental povertymeasure. Interested instructors can find detailed information at the U.S. Census Bureau website’s“Poverty” section under “Supplemental Poverty Measure: Latest Research” (2011).

Although most textbooks on the principles of economics contain a chapter devoted topoverty and income distribution, a very helpful choice for background reading is BradleySchiller’s student-friendly textbook, The Economics of Poverty and Discrimination (10th ed.,Pearson/Prentice-Hall, 2008).

REFERENCES

Blank, R. M., and M. H. Greenberg. 2008. Improving the measurement of poverty. Discussion Paper 2008-17 (De-cember). Washington, DC: The Brookings Institution, The Hamilton Project. http://www.brookings.edu/papers/2008/12 poverty measurement blank.aspx (accessed September 30, 2011).

Citro, C. F., and R. T. Michael. 1995. Measuring poverty: A new approach. Washington, DC: National Academy Press.Economic Policy Institute. 2008. Family budget calculator. Economic Policy Institute, Washington, DC. http://www.epi.

org/content/ budget calculator/ (accessed May 20, 2011).Fisher, G. 1997a. The development of the Orshansky poverty thresholds and their subsequent history as the official

U.S. poverty measure. Poverty Measurement Working Paper Series. Revised. Washington, DC: U.S. Census Bureau.http://www.census.gov/hhes/povmeas/publications/orshansky.html (accessed May 12, 2011).

———. 1997b. From Hunter to Orshansky: An overview of (unofficial) poverty lines in the United States from1904 to 1965. Poverty Measurement Working Paper Series. Revised. Washington, DC: U.S. Census Bureau. http://www.census.gov/hhes/povmeas/publications/ povthres/fisher4.html (accessed May 12, 2011).

Fuchs, V. 1967. Redefining poverty and redistributing income. Public Interest 8:88–95.Rector, R. 2010. Obama’s new “poverty” measurement. National Review Online, March 8. http://www.nationalreview,

NewYork,NY.com/articles/229274/obamas-new-poverty-measurement/robert-rector?page=1 (accessed September30, 2011).

Ruggles, P. 1990. Drawing the line: Alternative poverty measures and their implications for public policy. Washington,DC: Urban Institute Press.

Schiller, B. 2008. The economics of poverty and discrimination. 10th ed. Upper Saddle River, NJ: Pearson/Prentice-Hall.Short, K. S. 2010. Who is poor? A new look with the supplemental poverty measure. SEHSD Working Paper 2010-

15 (December 20). Washington, DC: U.S. Census Bureau. http://www.census.gov/hhes/povmeas/methodology/supplemental/research/SGE Short.pdf (accessed May 20, 2011).

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Smeeding, T. 2006. Poor people in rich nations: The United States in comparative perspective. Journal of EconomicPerspectives 20(1):69–90.

U.S. Bureau of the Census. 2011. Developing a Supplemental Poverty Measure. Federal Register. May 26, Vol. 75,No. 101, http://edocket.access.gpo.gov/2010/pdf/2010-12628.pdf (accessed May 15, 2011).

U.S. Census Bureau. 2011. Supplemental poverty measure: Latest research. Washington, DC: U.S. Census Bureau.http://www.census.gov/hhes/povmeas/methodology/supplemental/research.html (accessed September 30, 2011).

U.S. Department of Labor. 2010. Consumer Expenditure Survey, 2009: Current expenditure tables. Washington, DC:Bureau of Labor Statistics. http://www.bls.gov/cex/ (accessed May 5, 2011).

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