You can query the historical exchange rate of Asia-Pacific foreign exchange network: ynews/, where you can query not only Hong Kong dollars, but also other foreign currencies, and the retrospective time can reach 10 years. You can select what you need in the drop-down boxes of start time, end time and quotation respectively. For example, in May 2009, the exchange rate of Hong Kong dollars was 65,438+000 Hong Kong dollars to 88 yuan RMB.