After 1972, there were rapid advances in science and technology in Taiwan, one result being that pig breeders in Taiwan began using balanced, imported pig feeds. This resulted in less use of sweet potatoes. Moreover, irrigation works improved, and crop-rotation schemes were altered. Many who once grew sweet potatoes could switch to more profitable crops, so the acreage under sweet potato cultivation went down year by year.
民國六十年以後，由於大規模養豬戶興起，改用進口飼料；加上水利設施改善，輪作制度有所改變，許多原本種植甘薯的土地，陸續改種其他經濟價值更高的作物，所以耕地面積逐年減少。