Can you refer me to demographic data on newspaper comics section readership?

I’m looking for reliable data on the people who read the comics pages in daily newspapers. This would exclude traditional editorial page panels, but not the politically inspired strips such as Doonesbury. I am also not interested in numbers on video/DVD/TV cartoons of any kind. Referral to industry or trade publication data or scholarly research is valued over anecdotal, but I’ll gladly accept that, too. Thanks for any help at all!