A key measure of consumer confidence in the United States climbed in December to its highest level in two years amid some hopes that the country"s economic recovery will gather steam, according to a private research group Tuesday, according to dpa. The New York-based Conference Board"s index stood at 52.9 points in December, up from 50.6 for November. Optimism among businesses and the labour market helped push up the gauge. But consumers remained more downbeat about their income levels as they head into 2010, said Lynn Franco, director of research at the Conference Board.