1. National Health Commission. 2019 China Health Statistical Yearbook. Beijing: Peking Union Medical College Press; 2019.
2. Population Division, United Nations. World Population Ageing. 2001:1950–2050
3. National Bureau of Statistics. China’s 2010. Census Data; 2011. Available from: http://www.stats.gov.cn/tjsj/pcsj/rkpc/6rp/indexch.htm. Accessed December 19, 2019.