The impact of income inequality in America is more severe because it extends to education, explains Jared Bernstein of Salon.com. The issue, it appears, is not only that the difference between the low-income and high-income individuals is wide and getting wider, it's that the chief means to overcome it – education access – is growing wider, too.
Sean Reardon writes in The New York Times about the difference in standardized test scores based on income, and concludes that over the last 50 years the differences in scores between students from high income families and those from middle-class and low-income families has increased substantially from what it was 30 years ago.
To make this trend concrete, consider two children, one from a family with income of $165,000 and one from a family with income of $15,000. These incomes are at the 90th and 10th percentiles of the income distribution nationally, meaning that 10 percent of children today grow up in families with incomes below $15,000 and 10 percent grow up in families with incomes above $165,000.
In the 1980s, on an 800-point SAT-type test scale, the average difference in test scores between two such children would have been about 90 points; today it is 125 points. This is almost twice as large as the 70-point test score gap between white and black children. Family income is now a better predictor of children's success in school than race.
SAT scores aren't the only indicator where income appears to be playing an increasingly outsized role. Similar findings are being reported in other measures of education success such as college completion. The number of bachelor's degrees being granted to students from families in the top 10% of income distribution in the United States is up 18% over the last 20 years.
The number of degrees granted to children from families in the bottom 10% is only up 4 percentage points over the same period of time.
The most potent development over the past three decades is that the test scores of children from high-income families have increased very rapidly. Before 1980, affluent students had little advantage over middle-class students in academic performance; most of the socioeconomic disparity in academics was between the middle class and the poor. But the rich now outperform the middle class by as much as the middle class outperform the poor. Just as the incomes of the affluent have grown much more rapidly than those of the middle class over the last few decades, so, too, have most of the gains in educational success accrued to the children of the rich.