Thirty-one senior officials have been found guilty as of Monday of taking bribes since China launched a campaign to clean up government in late 2012, according to court rulings listed by China's anti-graft body.

The average bribe was 14 million yuan ($2.3 million). A wage-earner making 70,000 yuan a year in Beijing would have to work 200 years to make that much money.

The officials took a total of 440 million yuan in bribes. Six of them were ministerial-level officials, and the rest were at or above bureau level.

Former railways minister Liu Zhijun topped the list, taking 65 million yuan in bribes. He was sentenced to death with a two-year reprieve.

The court found that from 1986 to 2011, Liu took advantage of his positions as an official of local railway bureaus, as well as the former ministry of railways, and helped 11 people win promotions, project deals and cargo transportation contracts.

Fifty-three officials at vice-minister level or above have been investigated since late 2012, according to the Central Commission for Discipline Inspection.

The most recent case was decided on Monday with a senior political adviser from the Guangxi Zhuang autonomous region sentenced to 15 years in prison for taking 10.95 million yuan in bribes.

Li Daqiu, who held a vice-minister level post, seemed to be always successful in his career before he was investigated. He started work at age 18 as deputy Party chief of a village in Guangxi and worked as a Party chief at various levels throughout his 42 years in officialdom until he was promoted to vice-chairman of the Guangxi Committee of the Chinese People's Political Consultative Conference.

Li used his position to benefit 17 companies and individuals for 10 years from 2003, accepting 10.95 million yuan in bribes while he was Party chief in Hezhou and as vice-chairman of the region's political advisory body.

Yan Jirong, a professor with the School of Government at Peking University, said the court verdicts listed by the anti-graft body shows the central government's determination to deal with corruption and zero tolerance of officials misusing public power.

Officials in top positions have the power to decide the fate of major projects or industries and they are prone to corruption, Yan said.

"China hasn't established efficient procedures to supervise government power, which is often being misused by 'heads' at different levels of government organs to gain personal benefits," he said.

Investigations are continuing into 77 cases in Hainan province and 33 in Tianjin municipality involving top leaders at various levels. The anti-graft body in Shandong province has investigated 16 cases related to corrupt officials at bureau level.

Yan believes it is hard to curb corruption when the government role is not yet clearly defined in economic development, consequently it gives more space for the top officials to gain benefit with public power.

"With China's further reform in its economic development, there is an urgent need to set up more efficient market mechanisms to avoid too much government interference in the economy and build real transparency in every major decision-making step by the authorities," he said.

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