(Yicai Global) Sept. 12 -- Firms from the energy sector took the top three spots in the latest rankings of China's 500 biggest companies, while banks ranked in the highest profit margins and coal and steel producers took the heaviest losses, Jiemian News reported, citing data from the Chinese Enterprise Confederation and China Enterprise Directors Association.

The total operating income at all firms was CNY64 trillion (USD9.8 trillion) last year, making up 86 percent of the country's total gross domestic product for the period. Net profits totaled CNY2.83 trillion (USD435.4 billion), up 3.2 percent on the year, the list shows.

State Grid Corp. of China, China Petrochemical Corp. (Sinopec) and China National Petroleum Corp., all state-owned, topped the list in terms of operating income. The State Grid pulled in CNY2.09 trillion, Sinopec CNY1.97 trillion and China National Petroleum CNY1.87 trillion.

The list showed that banking was the most lucrative business. Seven banks were among the 10 most profitable Chinese firms, with Industrial and Commercial Bank of China Ltd. [SHA:601398;HKG:1398], China Construction Bank Corp. [SHA:601939;HKG:0939], Agricultural Bank of China Ltd. [SHA:601288;HKG:1288] and Bank of China Ltd. [SHA:601988;HKG:3988] outranking all other firms in terms of profitability.

Most of the biggest loss-makers came from the coal, steel and non-ferrous metal industries. Some 43 of the 500 firms posted losses last year, with 60 percent coming from the above three sectors.

The three hardest-hit firms were Ansteel Iron and Steel Group Corp., which lost CNY6.78 billion, Henan Energy and Chemical Industry Group Co., with losses of CNY5.1 billion, and Shandong Iron & Steel Group Co., which lost CNY4.47 billion.

However, the overall profitability in the coal, steel and non-ferrous metal sectors have improved relative to their performance in previous years, with losses reducing. This is mainly attributable to the fact that the government's overcapacity reduction measures are starting to have an impact.