http://www.nea.gov/news/news08/ArtistsinWorkforce.html 

The National endowment for The Arts did an interesting study a few years ago.It's about the numbers, income, distribution education and so forth of artists in America. Pay specific attention to fine artists to understand painter's survival, and income vs actors, writers, designers, and so forth   Above  is the link to their website and the article. I suggest you download the entire article ,and read the specifics on fine artists i.e. painters.