Stamp Tax Act Article 3

The dollar amounts provided in this Act shall be denominated in the national currency (yuan), which, for practical purposes, shall be converted into a comparable common currency issued under the authorization of the Central Government.
中文原文 印花稅法第3條
本法規定之金額,以國幣為單位。
其因事實上之需要而使用中央授權發行之通用貨幣者,應依政府規定之比價折算之。

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