The NSSF provides this kind of marketing research data, broken down to include pertinent information for your locale/region. If you're an NSSF member, the price is $250 ($500 for non members). This information is gathered from a professional marketing research company experienced in the firearms industry.
If you need market research data, it's an awesome bargain. Doing something like that on your own (presumably for your own purposes) inevitably leads to severe alcoholism, puppy kicking, and, in the sad end, registering with the Democratic Party.