A worker welds at a construction site in Yiliang, Yunnan province, February 28, 2015.[Photo/Agencies]

BEIJING -- Chinese industrial firms' profits further declined in August, indicating increased downward pressure on the economy.

Profits of China's major industrial firms fell 8.8 percent year on year in August, sharply down from a 2.9-percent decline posted in July, the National Bureau of Statistics (NBS) said on Monday.

The poor performance was mainly caused by drop in industrial goods prices due to weak domestic demand, a rise in unit costs, the stock market rout, and volatility in the yuan exchange rate, said He Ping, an official with the Department of Industry at NBS.

Profits of industrial companies with annual revenues of more than 20 million yuan ($3.1 million) totaled 448.1 billion yuan in August.

During the first eight months, industrial profits of the firms dropped 1.9 percent year on year to around 3.77 trillion yuan. The decline widened from the one-percent decrease registered in the Jan-July period.

Facing lingering downward risks, Chinese authorities have ramped up efforts to prop up the economy. The central bank has cut the reserve requirement ratio (RRR) of banks four times in nearly seven months and cut interest rates five times in nearly nine months.

Despite overall weakness, the manufactured goods inventory in August has been rising much more slowly than the previous month, which helped enterprises release inventory pressure and operation difficulties, He said.