U.S. Income Inequality

April 26, 2012

Income inequality in the United States has emerged as a popular topic in the media as well as the upcoming presidential election. The Occupy Movement has garnered a great deal of media attention in the past six months, with its premise of protesting economic and social inequality. The upcoming presidential debates are certain to feature a fair amount of political rhetoric in an attempt to address the issue of income inequality.

The chart above depicts the percentage of total income1 that the top 10% of earners (in 2010, families with a market income above $108k) are responsible for. As seen in the chart, the line forms a “U” shape where the top 10% accounted for approximately 45% of total income prior to WWII, declined to the low/mid 30’s until the late 1970’s and has risen to approximately 45% today.

In addition, we can use the GINI ratio (index of income concentration) to further scrutinize income disparity. The GINI ratio is a statistical measure of income equality ranging from 0-1. A measure of 1 indicates perfect inequality; i.e. one person has all the income and the rest have none. A measure of 0 indicates perfect equality; i.e. all people have equal shares of income. As also seen in the chart, the GINI ratio has also risen precipitously since its inception in 1967. Currently the GINI index stands at 0.47, which stands out as one of the highest when compared to other developed economies:

 

Germany 0.27
France 0.32
Italy 0.32
Canada 0.32
Japan 0.38
Uruguay 0.45
Russia 0.42
Singapore 0.47

There are many theories as to why we have seen such growth in income inequality since the late 1970’s. Potential explanations include:

  • Immigration of unskilled workers has put downward wage pressure on native born workers.
  • Advances in computers and automation may have replaced moderate to low skilled workers, thereby decreasing demand for these types of employees.
  • Decline of private sector labor unions and their ability to maximize incomes of their members.
  • Tax policy – corporate and individuals.
  • Relatively small increases in the minimum wage.
  • Corporate deregulation (in particular financials – 10% of corporate profits in 1970’s, 40% today – increase in executive compensation, prevalence of lobbyists).
  • Education gap between rich and poor has grown substantially. Cost of tuition is prohibitive for low income families. This has led to a shortage of highly skilled workers; therefore, demand (compensation) goes up for these types of workers.

The upcoming presidential debates will surely contain a healthy dose of discussion regarding income inequality, with a bulk focusing on tax policy and education reform. It will be interesting to see how each candidate plans to address these issues and the effect these policies will have on the financial markets. Is income inequality a detriment to the greater economy, or an essential part of capitalism?

_________________________________________________________________________________________________________

1 Income is defined as the sum of all income components reported on tax returns (wages and salaries, pensions received, profits from businesses, capital income such as dividends, interest, or rents, and realized capital gains) before individual income taxes. Government transfers such as Social Security retirement benefits or unemployment compensation benefits are excluded from the income definition. Non-taxable fringe benefits such as employer provided health insurance is also excluded from the income definition. Therefore, the income measure is defined as cash market income before individual income taxes.

The opinions expressed herein are those of Marquette Associates, Inc. (“Marquette”), and are subject to change without notice. This material is not financial advice or an offer to purchase or sell any product. Marquette reserves the right to modify its current investment strategies and techniques based on changing market dynamics or client needs.

Related Content

07.24.2026

2026 Halftime Market Insights

This video is a recording of a live webinar held July 23 by Marquette’s research team analyzing the first half…

07.22.2026

Under the Radar for the Second Half

The usual midyear version of these letters has touched on year-to-date performance as well as the most influential macroeconomic and…

Three-line chart showing cumulative returns for the KOSPI Index, SK Hynix, and SK Hynix Daily 2x Leveraged ETF from June 30, 2025 to June 30, 2026. While the KOSPI Index is at 137% cumulative, SK Hynix is at 671% and the ETF is at 948%, highlighting the growing role of ETFs. For full dataset, please contact marquettemarketing@marquetteassociates.com.

07.20.2026

Wagging the Dog

Our most recent Chart of the Week publication discussed how the AI investment opportunity has expanded beyond…

Seven-line chart showing cumulative return for Alphabet, Amazon, Meta, Samsung, SK Hynix, Microsoft, and Micron from January 2026 through July 10, 2026. Samsung, SK Hynix, and Micron have all outperformed other companies shown, highlighting the increasing demand for hardware in the current surge of AI-related infrastructure manufacturing. For full dataset, please contact marquettemarketing@marquetteassociates.com.

07.13.2026

The Modern Gold Rush

One of the enduring lessons of the California Gold Rush is that the greatest fortunes were often made not by…

Column chart showing share of private equity exit value by type in billions across acquisition, buyout, public listing, and continuation vehicles annually, 2016 to 2026 YTD. Since 2019, continuation vehicles have grown in share, with 2025 at their highest level of $98b. For full dataset, please contact marquettemarketing@marquetteassociates.com.

07.06.2026

To CV or Not to CV?

Since traditional exit routes have remained constrained in recent years due to higher interest rates, valuation gaps, and a subdued…

Stacked column chart showing income return and capital return for various infrastructure sectors. For full dataset, please contact marquettemarketing@marquetteassociates.com.

06.29.2026

Balancing Growth and Income in Infrastructure

This week’s chart highlights the varying return profiles across key infrastructure sectors by illustrating the split between income and capital…

More articles

Subscribe to Research Email Alerts

Research Email Alert Subscription

Research alerts keep you updated on our latest research publications. Simply enter your contact information, choose the research alerts you would like to receive and click Subscribe. Alerts will be sent as research is published.

We respect your privacy. We will never share or sell your information.

Thank You

We appreciate your interest in Marquette Associates.

If you have questions or need further information, please contact us directly and we will respond to your inquiry within 24 hours.

Contact Us >