Based on historical records from huizhou , this paper calculates the annual ratio of investment and profit on the absolute sales of paddy land was 6 . 67 % prior to the qianlong period 摘要清代徽州購買水田(絕賣)的年度投資回報(bào)率僅為6 . 67 % ,而所舉五個(gè)一般商業(yè)投資實(shí)例的年度投資回報(bào)率則在9 - 18 %之間。