Some old contracts have upwards of a dozen preceding contracts attached, spanning over a century of transactions, and today these are a valuable source of knowledge about the evolution of local place names. The multiplication of place names also helps researchers to know the level of development of a district at specific times, and indicates how Taiwan's cities took shape.
有的老契約的上手契可達十多份，年代從光緒到日據中期，一跨一百多年，連串這同一地區的歷年契約，不但可以研究地名一路的演變，從地名日益的增多現象，也可以看出開發程度的深淺及都市的形成。