Jan 8 The U.S. oil rig count this week dropped to the lowest level in over five years as energy firms stepped up the rate of idling rigs after one of the worst years in almost 30 years for drilling, data showed on Friday. Drillers removed 20 oil rigs in the week ended Jan. 8, bringing the total rig count RIG-OL-USA-BHI down to 516, the least since April 2010, oil services company Baker Hughes Inc said in its closely followed report.