The Enforcement Rules of the Land Tax Act Article 47

The total amount of land value increment as referred to under Article 31 of the Act, if already transferred after the original assigned land value, shall be determined according to the amount of the declared transfer value in excess of the declared present value at previous transfer upon ownership transfer or dien right establishment.
中文原文 土地稅法施行細則第47條
本法第三十一條所稱土地漲價總數額,在原規定地價後曾經移轉之土地,於所有權移轉或設定典權時,以其申報移轉現值超過前次移轉時申報之現值之數額為準。

English translation for reference only; the Chinese text prevails. Not legal advice.