Greg Mankiw outlines who earns the 0.1% of national income:
Here is an interesting paper that answers the question. Some highlights from Table 3 about the top 0.1 percent:
- 18 percent are financial professionals.
- 42 percent are executives, managers, or supervisors in nonfinancial businesses. More than half of those are in closely-held (presumably often small) businesses.
- 7 percent are lawyers.
- 6 percent are in medicine.
- 3 percent are in arts, media, or sports.
- Less than 1 percent are professors or scientists.
Note that this is only as of 2005 (my guess is financial professional income spiked as a percent of 0.1% of income from 2005 to 2008). It also doesn't show that the 0.1% earned 2.8% of all income in 1979, but 7.3% in 2005, or how much the above figures changed over the years. The latter is outlined below (i.e. the shift to finance was dramatic).