I care to remember the other day on a fairly long leg in the CRJ200 that at FL330 ISA deviation almost 0, MACH .74 and a full load we were burning right about 1300 lbs a piece. In the lower to mid 20's the burn is about 1450 lbs a piece. Also worn engines burn up to 14% more as far as I've seen. The ohter day we had an engine that was ready to be overhauled (could tell by the FF correction of 14%, spooling time, and ITT higher than normal). Also you burn about 3500-4000 lbs the first hour. A 15 min taxi is about 200lbs. It takes about 300lbs to shoot an instrument aproach with normal vectoring.