Assets at the Exchange Fund, which is used to back the Hong Kong dollar, totalled HK$3,589.9 billion ($462.9 billion) at the end of November, the Hong Kong Monetary Authority (HKMA) said on Friday. The figure was HK$3.5 billion lower than the total at the end of October, with foreign currency assets down by HK$36.1 billion while Hong Kong dollar assets were up by HK$32.6 billion, the city's de facto central bank said in a statement.