I fly DTW-MSP-BIL every week, the price of a first class ticket had been about $1100 vs about $500 for coach, with that price differential I have been flying nothing but first. Two weeks ago the price jumped to about $1800 so I checked on coach and booked my next sixteen segments for about $450 per trip. Just finished my first cycle and as a PE was bumped on all four segments, so my product remained the same and NW lost $650 per ticket on me. Sometimes I just don't get it!