Goldman Sachs: 18.17%
I have to admit that the GS number surprised me. I didn't think they were quite so rapacious, but indeed they are. In 2008, GS got whacked and saw it's net profits cut by a factor of 6, so they're not quite as consistently rapacious as Apple.
Exxon, meanwhile, is a proper capitalist firm, providing valuable goods and services that we all use and need for a reasonable price while employing lots and lots of American workers, paying them fair wages.