I am graphing the average combined federal taxes on our single earner family of four with three combinations of tax rates:
Income & Payroll (the employee part of social security and medicare)
Income & Payroll (both the employer and employee part of social security and medicare)
For comparison, you can see how the top marginal individual income taxes rates for the highest earners dropped since the 1950s while the social insurance taxes (i.e. the payroll marginal tax rates) increased.
Keep in mind the Tax Policy Center calculate these rates for:
4 person family including a married couple with one earner
Itemized deductions are assumed to equal 23 percent of income through 1986 and 18 percent of income thereafter