Here is a link to a non-partisan tax research foundation using census data to evaluate the share of income going to taxes:
The burden of all type of taxes on personal income as measured in this report is close to 40% in the 1970s-1998 period. Federal income tax is a sizeable, but less than 20% : http://www.taxfoundation.org/research/show/26371.html. State and local taxes are much smaller share of income: http://www.taxfoundation.org/research/show/336.html
The share of taxes going in personal income, depends on what is included in the taxes paid by citizen (which taxes) and how income is defined. A narrowly defined income variable can make the tax burden higher than a broader definition as well wh at taxes are included in the numerator of the burden ratio matters as you can see in the difference between share of all taxes paid to federal and state and local governments, versus the share of federal taxes in personal income.
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