It also instituted sweeping personnel changes, culminating in the elevation of two key supporters of Deng Xiaoping and the reform program, Hu Yaobang and Zhao Ziyang. In contrast to previous leadership changes, Hua would resign his posts one by one, although he remained on the Politburo until 1982. Hua was replaced by Zhao Ziyang as Premier of the State Council in September 1980, and by Hu Yaobang as Party General Secretary of the party in September 1982. The post of chairman was abolished to ensure that no one person could ever dominate the party as Mao Zedong had done. Until the mid-1990s, Deng Xiaoping was China's "de facto" Paramount leader, retaining only the official title of Chairman of the Central Military Commission, but not the chief offices of the State, government, or the Party. Meanwhile, Li Xiannian was appointed to the post of Chinese President, vacant since 1968. Li was a believer in central planning, and his appointment to this largely ceremonial position was a compromise move to appease conservative elements in the party.