It would be hard not to notice that we are living in a world of increasing inequality. According to data collected by the Federal Reserve, the share of the nation’s wealth owned by the top one percent of U.S. wealth holders increased almost 50 percent, from 22.8 percent in 1989 to 31.9 percent at the end of 2025.  Meanwhile, the gap between high and low earners has also been expanding.  One widely used measure is the ratio of wages of workers at the 90th percentile of the earnings distribution to those at the 10th percentile (the 90-10 gap).   According to the Bureau of Labor Statistics, the 90-10 gap was 3.7 in 1979 and grew to 5.0 by 2014, roughly where it is today. 

This widening gap helps us understand why robust economic growth has not translated into more positive views about the economy. GDP per capita, the conventional scorecard of economic performance, has more than doubled since the mid-1980s.  But, because of the growing income gap, this prosperity has not been widely shared.  For example, adjusted for inflation, the real compensation of production workers today is no higher than it was in 1979 (see MeasuringWorth.com). This marks a major shift.  In the 100 years from 1879 to 1979, the compensation of production workers grew at roughly the same rate as GDP per capita.

These facts both help us to understand our experience of the modern economy and raise a whole host of questions.  Why are the fruits of economic growth increasingly concentrated in the hands of the few?  Have there been other times when there has been a similar level of inequality?  What can we learn from past experiences?  What will happen in the future?