Fifty Years of Growth in American Consumption, Income, and Wages
By Bruce Sacerdote (Darmouth)
Abstract: Despite the large increase in U.S. income inequality, consumption for families at the 25th and 50th percentiles of income has grown steadily over the time period 1960-2015. The number of cars per household with below median income has doubled since 1980 and the number of bedrooms per household has grown 10 percent despite decreases in household size. The finding of zero growth in American real wages since the 1970s is driven in part by the choice of the CPI-U as the price deflator; small biases in any price deflator compound over long periods of time. Using a different deflator such as the Personal Consumption Expenditures index (PCE) yields modest growth in real wages and in median household incomes throughout the time period. Accounting for the Hamilton (1998) and Costa (2001) estimates of CPI bias yields estimated wage growth of 1 percent per year during 1975-2015. Meaningful growth in consumption for below median income families has occurred even in a prolonged period of increasing income inequality, increasing consumption inequality and a decreasing share of national income accruing to labor.
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Distributed by NEP-HIS on:2017-04-23
Revised by: Stefano Tijerina (Maine)
Contrary to the popular outcry that the gap between rich and poor in the United States has steadily increased since the 1960s and that the quality of life has steadily deteriorated, Bruce Sacerdote argues that the picture is not as grim and that the steady rise of household consumption for households “with below median income” is evidence that the national economy has continued to thrive for all U.S. citizens and not just those on the top. In “Fifty Years of Growth in American Consumption, Income, and Wages” Sacerdote reveals that the focus on wage growth favored by economists and policy makers impedes us from focusing on other aspects of growth, such as consumption and the quality of consumed goods. From his perspective focusing on real wage growth and the inflated rates of the Consumer Price Index (CPI) only tells half of the story and that it is therefore necessary to center on consumption data in order to construct a more holistic picture of the economic realities of the below median income household. From his perspective, “low income families have seen important gains in at least some areas of consumption” thanks in part to a steady growth in consumption of 1.7 percent per year since 1960.
Bruce Sacerdote adjusted the CPI to the bias corrections developed by Dora Costa and Bruce Hamilton who previously worked on similar questions, looking at “the true costs of living” and new ways of estimating “real incomes” in the United States. His findings for the period between 1960 to 2015 concluded that there was an increase of 164 percent in consumption for those below the median household income. A previous consumption measure for the same period of time, excluding the bias measures from Costa and Hamilton, showed a 62 percent increase in consumption. A third measurement that calculated real wages using the Federal Reserve’s Personal Consumption Expenditures (PCE) for the same period of time reversed the claims of wage stagnation furthered by some economists, policy makers, citizens, and labor union advocacy groups. This last measurement showed that when using the PCE to deflate nominal wages, the growth of real wages was 0.54 percent per year. This contradicts the arguments of data sets such as the “2016 Distressed Community Index” that focus specifically on the increasing gap between rich and poor in the United States.
Beside the bias corrections and other measurements, Sacerdote argues that the quality, technology, and durability of current consumption goods is superior to that of previous decades, therefore expanding the relative capacity of consumption of those below the median income. For example he claims that “the number of cars per household has risen from 1 to 1.6 during 1970-2015,” while the median home square footage for this income segment has risen about 8 percent during this same period of time.
His objective of focusing “on growth rates in consumption instead of changes in poverty rates” is achieved by using data and methodologies for analyzing data that shows that “the glass half full” but as it is evident from the working paper, quantitative data can be tailored to fit the researcher’s agenda. Numerous questions surface regarding consumption trends in the United States that lead to further conclusions that indicate that the 164 percent increase of the past fifty-plus years is the result of greater household debt and cheaper consumer goods prices that are tied to the impacts of globalization. Consumer households that fall below the median income continue to steadily consume more, there is not doubt about that, but their wages continue to depreciate while their debt continues to rise. Moreover, globalization has allowed companies to transfer their production overseas, leading to a loss of jobs in the manufacturing sector that potentially offered higher than minimum wage salaries to those households that ranked below the median income. The transfer of production has at the same time guaranteed cheaper products to these consumers that then are able to consume more with their lower wages and their greater access to loans that artificially maintain their consumption capacity while increasing their debt to income ratio.
According to the U.S. Census Bureau, the median household income for the year 2014 was $53,719. This means that half of Americans earned less than that amount. This population, that represents the central focus of Sacerdote’s research, currently has an average household debt of $130,000 (assuming that those earning below the median income are forced to go into debt to maintain their standard of living). The breakdown of this debt shows that mortgages, credit cards, auto loans, and student loans make up most of the American debt. This could indicate that the steady consumption increase demonstrated by Sacerdote could actually be artificially maintained by the financial system that keeps the American consumer afloat.
Sacerdote’s work could also benefit from qualitative research that would provide more in-depth analysis and at the same time counter-balance his claims on consumer choice and the reliability of products being consumed. Qualitative research could provide a different explanation as to why low-income consumers have opted to hold on to their vehicles for longer periods of time, how they are able to purchase expensive technology such as cell phones and access services such as internet and cable television, if indoor plumbing is a sign of a higher quality of life or simply a response to policy and the standardization of construction norms, and if the increase in housing square footage per household really represents a higher quality of life.
Selectivity of data and research approach in this case clearly benefits the researcher’s argument but this could quickly be turned around with other sets of data and a different research approach. A focus on credit rates and debt rates over the same period of time shifts the argument around and leads to completely different conclusions, and so would a qualitative analysis of the quality of life of Americans. Although controversial, Sacerdote’s work forces the reader to think more critically about the changes that have taken place in American society in the past fifty-plus years and brings up the question of whether or not this consumption approach is more reflective of the nation’s economic dependence on consumer consumption as a percentage of the GDP.
 See for example Thomas Piketty’s argument on the increasing gap between rich and poor and the possible threat to capitalism and democratic stability in “Capital in the 21st Century.” Cambridge: Harvard University (2014).
 Bruce Sacerdote. “Fifty Years of Growth in American Consumption, Income, and Wages.” National Bureau of Economic Research, working paper series, working paper 23292, March 2017. Accessed April 25, 2017. http://nber.org/papers/w23292, 2.
 Ibid., 1-7.
 See Dora L. Costa. “Estimating Real Income in the United States from 1888 to 1994: Correcting CPI Bias Using Engel Curves.” Journal of Political Economy 109, no. 6 (2001): 1288-1310, and Bruce W. Hamilton. “The True Cost of Living: 1974-1991.” Working paper in Economics, The John Hopkins University Department of Economics, January 1998.
 Sacerdote. “Fifty Years of Growth in American Consumption, Income, and Wages,” 2.
 Ibid., 1.
 Ibid., 3.
 “2016 Distressed Community Index: A Analysis of Community Well-Being Across the United State.” Accessed April 25, 2017. http://eig.org/dci/report. See also for example Gillian B. White. “Inequality Between America’s Rich and Poor is at a 30-Year High.” Washington Post, December 18, 2014. Accessed May 1, 2017. https://www.theatlantic.com/business/archive/2014/12/inequality-between-americas-rich-and-americas-poor-at-30-year-high/383866/.
 Sacerdote. “Fifty Years of Growth in American Consumption, Income, and Wages,” 2.
 Matthew Frankel. “Here’s the Average American Household Income: How do you Compare?” USA Today November 24, 2016. Accessed May 2, 2017. https://www.usatoday.com/story/money/personalfinance/2016/11/24/average-american-household-income/93002252/
 Matthew Frankel. “The Average American Household Owes 90,336 – How do you Compare?” The Motley Fool May 8, 2016. Accessed May 10, 2017. https://www.fool.com/retirement/general/2016/05/08/the-average-american-household-owes-90336-how-do-y.aspx