Singapore and Hong Kong are the world's most competitive economies, an annual survey said Friday, relegating the United States from the top spot for the first time since 1993. The study lists 58 economies according to 328 criteria that measure how the nations create and maintain conditions favorable to businesses - a formula that had favored the US for 16 years. “They are so close in the rankings, that it would be probably better to define them as a leading trio,” said Stephane Garelli, professor at the Lausanne, Switzerland-based IMD business school, publisher of the World Competitiveness Yearbook. Despite high unemployment and debt, and continued market instability, the United States was better placed than European nations and others to attract new investments and help companies grow. “The US has weathered the risk of the financial and economic crises thanks to the sheer size of its economy, a stronger leadership in business and an unmatched supremacy in technology,” Garelli said. Switzerland and Australia rounded out the top five. Then came Sweden, Canada, Taiwan, Norway and Malaysia. China continued its rise in the survey, reaching 18th and highlighting that it is no longer dependent on foreign markets buying up its cheap exports. It led fellow emerging economies India, 31; Brazil, 38; and Russia, 51. Debt-laden Greece actually improved in the 2010 ranking, rising six places to 46th. Venezuela ranked last for the fifth year in a row, preceded by Ukraine, Romania, Argentina and Croatia.