I'm skeptical of that. There is one web site (besides the above comment) that has this quote. It links to the Wikipedia article about James Simons as its source. The Wikipedia article does not seem to mention the quote. Even if James Simons did say that, I'd like to see his source.
Edit: it just occurred to me that, since we are talking about "average" and not "median", this may as well be true, if a handful of mathematicians make a gazillion dollars a year. Very senior faculty members in the top research universities in the US are likely to make only $200-500k per year.
Edit: it just occurred to me that, since we are talking about "average" and not "median", this may as well be true, if a handful of mathematicians make a gazillion dollars a year. Very senior faculty members in the top research universities in the US are likely to make only $200-500k per year.