"Income inequality refers to the extent to which income is distributed in an uneven manner among a population. In the United States, income inequality, or the gap between the rich and everyone else, has been growing markedly, by every major statistical measure, for some 30 years." This article gives an in-depth description of the issue of income inequality, comparing different income-related statistics to those of earlier decades. It also informs of how this issue is progressively becoming less of a problem, but still needs to be addressed.

"The middle class - those who make between $50,000 and $100,000 - account for 22% of all filings and roughly the same in income, at 25%. Put it another way: 3.6 million households make basically the same as 32 million households." This article describes income equality in America, measuring it using statistics of taxes. It also explains the annual incomes of the upper and lower classes.