N日平均换手率=N日成交量总和(比例复权)/流通股本/交易天数
//取得万科A从20120419起往前推共5个交易日的平均换手率
SetSysParam(pn_stock(),'SZ000002');
SetSysParam(pn_cycle(),cy_day());
SetSysParam(pn_date(),inttodate(20120419));
return StockAveHsl2(5);
//结果:0.459
StockAmountSum2 StockHigh2 StockHighAmount2