By conventional measures, China's economy is roaring ahead at a growth rate of more than 10%. But an unusual report by the Chinese government suggests the nation's growth -- while swift -- may not be quite as dazzling as it seems. Last month, Beijing released the results of a two-year "green accounting" study indicating the nation's rampant pollution problem is quietly undermining long-term economic growth. According to the report, pollution cost the country $64 billion in 2004, the equivalent of three percentage points of economic output.