NEW YORK (AP) — The price of oil will finish 2011 about 8 percent higher, after concerns about tighter global supplies dominated energy markets throughout the year.

Benchmark crude, which on Friday fell 30 cents to $99.35 per barrel in morning trading in New York, started the year at $91.38 per barrel. Prices surged in February as unrest in Libya cut off 1.5 million barrels of oil exports. After a summertime slump, they rose to $100 per barrel as traders are closely watching tensions between Iran and Western powers over Tehran's nuclear power program.

Iran threatened this week to close the key oil export passage of the Strait of Hormuz in the Persian Gulf if the U.S. and other nations tighten sanctions. The U.S. Navy said it would not tolerate any move to limit the strait's traffic.