Tongyong Pinyin was the official romanization system in Taiwan, but its use was voluntary. The romanization system that one encounters in Taiwan varies according to the government authority that administers the facility. Street signs in most areas use Tongyong Pinyin, including the cities of Kaohsiung, Tainan, and surrounding counties. A contrast could be seen in the two entities that now make up the municipality of Taichung–Taichung County used Tongyong Pinyin while Taichung City has used Hanyu Pinyin since at least 2004. Then-mayor Ma Ying-jeou remained committed to using Hanyu Pinyin as the Romanization standard for Taipei. Taipei County (now New Taipei City) used Tongyong Pinyin, but in Taipei Metro stations, Tongyong Pinyin was given in parentheses after Hanyu Pinyin. Modified Wade–Giles spellings are popularly used for many proper names, especially personal names and businesses.