The wealthiest 1 percent of the population earn 19 percent of the income but pay 37 percent of the income tax. The top 10 percent pay 68 percent of the tab. Meanwhile, the bottom 50 percent—those below the median income level—now earn 13 percent of the income but pay just 3 percent of the taxes. These are proportions of the income tax alone and don't include payroll taxes for Social Security and Medicare.
And a short history of tax cuts and their impact on the percentage paid by the rich:
In the early 1960s, the highest marginal income tax rate was a stunning 91 percent. That top rate fell to 70 percent after the Kennedy-Johnson tax cuts and remained there until 1981. Then Ronald Reagan slashed it to 50 percent and ultimately to 28 percent after the 1986 Tax Reform Act. Although the federal tax rate fell by more than half, total tax receipts in the 1980s doubled from $517 billion in 1981 to $1,030 billion in 1990. The top tax rate rose slightly under George H. W. Bush and then moved to 39.6 percent under Bill Clinton. But under George W. Bush it fell again to 35 percent. So what's striking is that, even as tax rates have fallen by half over the past quarter-century, taxes paid by the wealthy have increased. Lower tax rates have made the tax system more progressive, not less so. In 1980, for example, the top 5 percent of income earners paid only 37 percent of all income taxes. Today, the top 1 percent pay that proportion, and the top 5 percent pay a whopping 57 percent. (emphasis added)
In related news, Harvard will start offering more financial aid to families earning up to $180,000 a year.