Weighty salaries for high-up managers of state-owned enterprises can be attributed to monopolies those companies have, said a recent report on the salaries of senior officials at listed companies.

The report, issued by Beijing Normal University on Sunday, is based on the research of more than 1,700 listed companies on the Chinese mainland in 2010, said Du Wencui, the assistant director of the Research Center for Corporate Governance and Enterprise Development with the university.

"The report puts the average annual salary of the top three highest paid managers at China National Petroleum Corporation (CNPC) at 1.1 million yuan ($173,470), which is excessively high," Du told the Global Times.

The report said the high revenues of State-owned companies, such as CNPC, are due to their monopoly statuses.

Citing CNPC rented 1.145 billion square meters of land from 2007 to 2010 for 2 billion yuan, Du said it was too low, at about 2 yuan per square meter. The CNPC enjoys a low tax rate on natural resources enabling it to acquire crude oil and gas at low prices, Du siad. It also receives a yearly subsidy from the central government, the report said.

Without these advantages, CNPC's actual revenue would have been substantially lower, the Beijing News reported yesterday.

In 2010, the company's nominal revenue was nearly 193.1 billion yuan, but its actual profit was almost 36.7 billion yuan, or 19 percent of the nominal revenue, said the report.

Apart from the high-ranking administrative managers, regular staff at State-owned enterprises also benefit from monopolies, said Du. But the salaries of senior managers at State-owned companies are five times ordinary staff members, while at private companies the ratio was seven to one, Du cited.

According to the report, annual salaries ranged from 24,000 yuan to 74.6 million yuan. The average salaries of senior managers at listed companies is 740,770 yuan.