New York City fell seven spots to No. 22 on the list of the world’s most expensive cities, according to data compiled by human resources consulting firm Mercer. The drop was attributed to the weak U.S. dollar and decline in housing prices. New York was the only U.S. city in the top 50, with Los Angeles at No. 55, Miami at No. 75 and Washington, D.C. at No. 107. Taking the top three spots were Moscow, Tokyo and London.