China's major industrial firms posted faster profit growth in the first three quarters of this year, the National Bureau of Statistics (NBS) said Friday.

Industrial companies with annual revenue of more than 20 million yuan (3 million U.S. dollars) reported profits of 5.58 trillion yuan in the first nine months, up 22.8 percent from a year earlier, the NBS said in a statement.

The growth was faster than the 21.6 percent in the January-August period, and 21.2 percent in the January-July period.

In September alone, profits of major industrial firms rose 27.7 percent year on year, much faster than the 24-percent growth in August and 16.5-percent in July, it said.

Among the 41 industries surveyed, 39 posted year-on-year profit growth in the first three quarters.

Companies in power, liquor, and electronics industries saw rapid growth, together contributing 3.8 percentage points to the uptick in growth pace in September compared with last month.

NBS statistician He Ping attributed the rapid growth partly to faster expansion in both production and sales as well as price increases in industrial products.

In September, China's industrial output rose 6.6 percent year on year, higher than the 6-percent growth in August. Revenue from main business of industrial firms rose 10.8 percent, also higher than the rate registered a month ago.

China's producer price index (PPI), which measures costs of goods at the factory gate, rose 6.9 percent year on year in September, 0.6 percentage points higher than the August level.

The price rebound has added some 652.6 billion yuan to the operating income of industrial firms, resulting in a net increase of 136.2 billion yuan in profits after costs were deducted.

He also said that profitability of the companies has improved with lower costs and expenses. In the first nine months, costs per 100 yuan of revenue dropped 0.23 yuan from the same period last year, while expenses per 100 yuan of revenue also went down 0.27 yuan.

The leverage ratio, a measure of financial risks, also went down amid the government's ongoing deleveraging efforts. By the end of September, the debt-asset ratio of the firms dropped 0.6 percentage points from a year ago to 55.7 percent.