Enforcement Rules of the Household Registration Act Article 23

The areas and periods of census shall be prescribed by municipal and county (city) governments, and shall be submitted to the central competent authority for examination and filing.
中文原文 戶籍法施行細則第23條
戶口清查之區域及期間,由直轄市、縣(市)政府訂定,報中央主管機關備查。

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