It decreased due to the fact that many jobs were opening in the urban areas so people left their farms and houses in rural areas to get a job in a bigger city.
The answer to the question is True, I has the same one just a few days ago
1949–1976: Socialist transformation under Mao Zedong. Following the Chinese Civil War and victory of Mao Zedong's Communist forces over the Kuomintang forces of Generalissimo Chiang Kai-shek, who fled to Taiwan, Mao declared the founding of the People's Republic of China on October 1, 1949.