In some cases, the official records show that there was only 1,000 jia of land under cultivation in a certain district, whereas a contemporary contract reveals that at least 3,000 jia were being farmed.
有時史籍上記載一個地方已開墾報稅的田才一千多甲，然而所發現的單一張老契約，就說明瞭當地已有三千多甲地在墾殖。