How old are you guys?

I notice some intelligent individuals on Yahoo answer forums lately; mostly of whom were "Top Contributors". They range from writing, mathematics, humanities. I just wanted to know how old are you guys. You can choice not to answer, if you don't want to. It just that, I wanted to know the age range of my Yahoo counterparts. I'm 19, my strong subjects on yahoo would be writing blogs, prior to grammar correction and sentence structures, and mathematics. I haven't been active lately, therefore I lost my yahoo "top contributor" logo.