Folding in Blinds to a steal

I've been playing solely NLHE tourneys now for about 3 months after a year of playing limit cash games, which I finally got bored stupid with. About 95% of my games are SnG's and most of these are $10 games at Pokerstars. I'm showing a 33% ROI and about 45% in the money finishes, which to me is OK, but with room for improvement. In fact I'm thinking of stepping up to $20 games on a regular basis (played 3 so far, one 3rd place), but would like to iron out any kinks in my armour before doing so.

One stat that slaps me in the face is my frequency of folding in the blinds to a raise, but being a relative rookie, I don't know if these are good or bad. My initial reaction is that they are bad, but would appreciate the views of more seasoned players (You there Mr Harrington?).
My stats show:
Folded SB to steal 86.24%
Folded BB to steal 65.04%

I play tight especially early on which is borne out by the fact that my folding % goes down as the blinds go up.

Are these the sort of figures that show good tight play or am I being a wimp?