I really .... no, REALLY wish that charts like that would 'hit the toilet' at full afterburner velocity.
The so-called 'Social Security' and 'Medicare' taxes ARE part and parcel of FEDERAL INCOME TAX - and are ALWAYS blatantly missing from these types of pseudo-analysi.
The FACT is that the MIDDLE CLASS in this country PAYS THE MAJORITY of the 'taxes' in this country - and the poor, not-so-poor, and super-rich skate.
The FOURTEENTH AMMENDMENT is CONSTANTLY violated by these preferential 'tax treatments'.
Yeah, the 14th - that's the one that deals with 'equal treatment under the law'.