BEIJING - China's major industrial firms reported slower profit growth in the first 11 months of this year, the National Bureau of Statistics (NBS) said Wednesday.

Businesses with annual revenue of more than 20 million yuan ($3 million) reported profits of 6.88 trillion yuan in the first 11 months, a 21.9-percent increase from one year earlier, the NBS said in a statement.

The growth marked a mild slowdown from 23.3 percent in the January-October period. In November alone, the profits were up by 14.9 percent, down from 25.1 percent during the previous month.

NBS statistician He Ping said slowing price growth bit into corporate profits. "Primary calculation showed price changes...reduced profits by 94.4 billion yuan month-on-month, dragging down the profit increase by 13.8 percentage points."

But He stressed that business performance continued to improve, citing dropping costs, faster capital turnover and lower corporate leverage.

Industrial profit margins rose to 6.36 percent, up 0.54 percentage points year-on-year. The debt-asset ratio, which measures the business debt burden, dropped to 55.8 percent by the end of November from 56.3 percent a year ago, due to government efforts to defuse financial risks.

In a breakdown of 41 industries surveyed, 39 posted profit increases during the first 11 months, and only 2 logged shrinking profits.

Coal, ferrous metal, chemicals, oil and natural gas contributed 52.8 percent to the total profit increase. Profits in coal mining and cleaning more than tripled that of a year ago, the fastest, followed by machine repairing and ferrous metal.