WTI differentialWell of course i do not know but if i was to speculate on a possible reason it would be............we are probably in the middle of refinery fall shut downs ..........this may be causing a bunch of oil to be put into storage tanks at cushing ot where ever else they store it until such time as refineries are back at it..........refineries have been running hot all summer so they might need more work than usual........no new refineries built in usa in quite sometime as you are probably aware.........makes for a real bottleneck when demand is strong