You should exclude SS and Medicare when talking about income tax rates. Both of these are basically forced-savings, not taxes. You pay in (save) when working, you get the money back when you retire in the form of SS payments and medicare coverage. Obviously that's a bit of simplification as todays payroll deductions directly fund today's retirees, but the general idea is correct. Unlike taxes, you will more-or-less get back what you put in when you retire. You can't lump income tax and these two force-savings together when talking about tax burden.