Starting from the 1990s, the demographics of the Chinese American community have shifted in favor of immigrants with roots in mainland China, rather than from Taiwan or Hong Kong. However, instead of joining existing Chinese American associations, the recent immigrants formed new cultural, professional, and social organizations which advocated better Sino-American relations, as well as Chinese schools which taught simplified Chinese characters and pinyin. The National Day of the People's Republic of China is now celebrated in some Chinatowns, and flag raising ceremonies feature the Flag of the People's Republic of China as well as the older ROC flag. The effects of Taiwanization, growing prosperity in the PRC, and successive pro-Taiwan independence governments on Taiwan have served to split the older Chinese American community, as some pro-reunification Chinese Americans with ROC origins began to identify more with the PRC.