SIEGEL: And if we looked at, say, the top 20 percent, the top fifth of all incomes in the U.S., who would that be and how much do they pay?
Mr. WILLIAMS: The top fifth starts a little bit above $100,000. That group makes about 56 percent of all income and pay about 70 percent of all taxes.
SIEGEL: So when it comes to the federal income tax, at least, we have a progressive system. The more you make, the more you pay. The less you make, the less you pay. But we pay other taxes, most notably the federal payroll tax. How many Americans pay more in payroll tax, FICA tax, than in income tax?
Mr. WILLIAMS: If you consider both the share paid by the employee and by the employer, which most economists think is borne by the employee, about 75 to 80 percent of us pay more payroll tax than income tax. Only 13 percent don't pay either one of the taxes a far cry from the 47 percent who get out of the income tax.
SIEGEL: And for what percent is there actually a negative income tax? What percent is actually benefitting from, say, the earned income tax credit so that the federal government is giving them money?
Mr. WILLIAMS: We estimate perhaps 40 percent of more of Americans are getting some money back. That's because we've made a number of the credits refundable. So if it takes your taxes down to zero, it can take it below zero and result in a payment.
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