Crude oil prices rally as spending drops in exploration and production side of the global energy sector. UPI/Gary C. Caskey NEW YORK, Feb. 6 (UPI) — Crude oil prices extended their rally Friday, posting some of the biggest two-week gains in recent trading as markets show signs of moving above a floor price. The price for West Texas Intermediate, the U.S. crude oil benchmark, gained 2.75 percent from the previous session to trade at $51.87 per barrel for the March contract early in the trading day. WTI started the year at $52.69 before falling more than 15 percent by the end of January. Prices since the start of February are up nearly 7 percent. Crude oil prices have lost about half of their value since June as markets swing toward the supply side, driven in large part by a weak global economy and increased production from the United States. […]