Rather than try to explain what I'm talking about, I'll just attach an image. They're worth 1000 words you know. I really have to hand it to myself for my mspaint skills.
It's possible that what I think is normal really isn't, but I've seen that general shape on graphs in a few places.
So my question, is what does my graph indicate? My first guess is a lack of muscular strength. Do I need to hit some weights?