Oil ends down on profit-taking but still up strongly on week

Oil prices fell on Friday as investors cashed out big weekly profits after a rally driven by disruptions to crude supplies and Wall Street's gains from U.S. economic data. Prices turned negative soon after the release of weekly U.S. oil rig data by industry firm Baker Hughes that showed a 10th weekly drop in the rig count. "I think a good part of the selling was due to cashing out of winning positions people had established earlier in the week," said David Thompson, executive vice-president at P