My hold'em manager chart shows my win without showdown to be pretty damn negative.

I have an overall + monies at 25NL but all the money comes from showdown and without showdown is like a straight line downwards.

Is this because i fold too much? Or do i not try to bet draws out of my made hands enough?
I'm obviously not too fussed as long as i keep making money but i feel it's a leak and i don't know what to do to stop it. I make TPTK laydowns against unknown facing aggression etc; should i be more prepared to risk my stack and make notes after?

Clar