Well, there are a "whopping" 1500 new naturalised citizens since the passage of 1998 citizenship law :)

https://www.hrichina.org/en/content/4573 http://foreignpolicy.com/2010/04/13/the-myth-of-one-china/

In practice, naturalizing as a Chinese national is extremely rare, even more so when the sheer population of the region is taken into account and compared to other comparable regions, such as the European Union, United States and India. Majority of foreign permanent residents simply remain that for the duration of their residency, without ever being asked or forced to naturalize. During the Fifth National Population Census (2000), only 941 naturalized citizens that do not belong to any of Communist Party of China's recognized 56 indigenous ethnic groups (which already includes Koreans, Vietnamese, and Russians)[13] were counted in China's mainland.[14] As of 2010, the total number of naturalized Chinese was only 1,448 in Mainland China, out of the population of over 1.33 billion. In 1990, there were over 3,000.[15]

More foreigners have applied for naturalization as Chinese nationals with permanent residency of Hong Kong since the handover in 1997. Among Hong Kong residents from 1997 to 2012, 3,411 Pakistanis, 3,399 Indonesians, 2,487 Indians, 1,115 Vietnamese, and 387 Filipinos have been naturalized.[16] One case of mass naturalization occurred in 2003, when less than 200 Damans, an ethnic-Nepali people who had resided in Gyirong County of Tibet for over two centuries, were granted Chinese nationality. The serial numbers on their naturalization certificates suggested that around 4,000 people (including the Damans) had naturalized as Chinese nationals in Mainland China until 2003.[17]