I can't remember where I got this figure (the forum at ProBlogger?) that says only one out of every 100 readers you have will also be a commenter. I figure it's more of a hyperbole than a decent estimate. Or if it is any way accurate, then that's for blogs with a lot of traffic and a great number of lurkers. Then again, the 100 "readers" could include people who stumble upon one post, read it and like it, but then never come back.
What do you think? And is there any way to calculate general readers vs. commenter statistics?