In 2011, it took $389K or more of adjusted gross income to make it into the top 1% of income earners, and they paid 35% of all federal income taxes. The top 5% of income earners made at least $168K and paid almost 57% of all federal income taxes. The top 10% paid made at least $120K and paid 68%. The top 25% included all those making $70.5K or more, and they paid 86% of all federal income taxes. Meanwhile, the bottom 50% of income earners (those making $35K or less) paid only 3% of all federal income taxes, and the vast majority of them either paid no income tax or received money on net from the IRS.
The Laffer Curve at work: Although the share of total income taxes paid by the top 10% of income earners today has fallen a bit in recent years, it has nevertheless risen by over 40% since the early 1980s, despite the fact that the top income tax rate has been cut in half. Slashing the top marginal rate by half resulted in a huge increase in the share of total income taxes paid by the rich.
Instead of asking the rich to pay even more, we should be thinking about how everyone should pay at least something. Just paying your social security taxes doesn't count, because in theory—if not in practice, since the rich will undoubtedly subsidize the social security income of a great many people in the future when social security revenues fail to cover expenditures—that is money you will get back when you retire. Income taxes, in contrast, go into the general fund.
The chart below shows the share of total income (AGI) earned by each of the groups in the chart above. Not surprisingly, top income earners make a large share of total income. However, if you compare the two charts, you see that the share of total taxes they pay is much larger than the share of income they earn. Our tax code is very progressive no matter you look at it. In 2011, for example, the top 1% of income earners made 19% of the country's total adjusted gross income and paid 35% of total income taxes. The top 5% earned 34% of total income and paid 57% of total taxes. The top 10% earned 45% of total income and paid 68% of total taxes. The top 25% earned 68% of total income and paid 86% of total taxes.