Are you sure you looked at the table? Chemistry and Mathematics are in the upper half of the table, i.e. higher earnings.
I meant that for a major that's generally considered to be hard and lead to a lucrative career (it's part of "STEM" after all), it's not that different from Pol Sci or Business (and it does worse than Accounting or Economics, both of which are non-STEM), which most people probably wouldn't expect.
I would expect (but do not have data to support) that those who do accounting/econ who take a more math-oriented approach do better than those who take a less math-oriented approach.