Thirty percent of the gains of China's state-owned capital will have to be handed back to the government by 2020, according to a decision issued on Friday by the Central Committee of the Communist Party of China (CPC).

At present, the proportion ranges from zero to 15 percent. The money will be used to improve people's livelihood, said the decision.

The lengthy policy document -- officially named "a decision on major issues concerning comprehensive and far-reaching reforms" -- was approved by the Third Plenary Session of the 18th CPC Central Committee, a four-day key meeting which ended on Tuesday.