text: With regard to Federal income tax, anyway, very, very little.  The top 5% of wage earners pay 54.36% of all Federal income tax.  The top 50% pay 96.54% of all Federal income tax. (the median income being roughly $44,000, depending how you calculate).  There are rougly 300 million Americans, so there are 150 million (which, I'm sorry, does include children), paying a total of $25.9 million in taxes.  There are, if it helps, approximately 12 million people between the ages of 15 and 17.  I'm sorry my numbers are dead-on precise, but I don't have detailed breakdowns at hand.