Houston, Feb 20: The oil rig count continued its downward trend in the United States this week with only 413 still operating, a leading oil field service company said. The number of oil rigs in the country this week fell by 26, and the number of oil and gas rigs totalled 514, the lowest point since the last century, specifically 1999 when the country had 488 rigs, Xinhua cited Friday's data released by Baker Hughes, one of the world's largest oil field services companies, as saying.