U.S. hotel rates paid by American Express Business Travel clients remained flat overall in 2010 compared with 2009 but reached peak levels for the year during the final three months

, according to the travel management company. The average domestic hotel rate for the full year was unchanged at $152 while the average international rate was down $2 to $236. Fourth-quarter rates averaged $164 domestically and $244 internationally, both up slightly from 2009 levels. Fourth-quarter U.S. increases included 12 percent in Las Vegas and 5 percent in Denver, New York, San Francisco and Washington.