BEIJING, May 2 (Xinhua) -- China's listed firms saw net profits jump by nearly 20 percent last year, the best performance since 2010, thanks to ongoing economic reform that boosted commodity prices and improved earnings.

The 3,504 companies listed on the Shanghai or Shenzhen stock exchanges posted combined net profits of 3.35 trillion yuan (about 530 billion U.S. dollars) in 2017, up 19.2 percent year on year, the China Securities Journal reported, citing data from financial information provider Wind.

Among them, more than 2,200 firms reported higher net profits than the previous year, while profits of 1,168 firms were up by more than 30 percent.

The listed companies also reported an 18.7 percent rise in business revenue in the past year, and those from non-banking finance, food and beverages, recreational service, medical biology and real estate sectors had the highest gross profit margin.

Steel, coal and other cyclical industries reported the fastest annual growth in profits last year, as supply-side structural reform has prompted a rebound in commodity prices.

Boosted by the price rise, mining companies, steel and non-ferrous metal producers, mechanical equipment manufacturers saw net profits more than doubled in 2017.

Most listed firms extended their good performance into the first quarter of 2018, as more than 60 percent of the listed companies reported profit growth.

The improvement in corporate profits came amid a solid economic expansion in the first three months, when the Chinese economy kept its resilience of last year with a 6.8-percent year-on-year growth.

In 2017, China's GDP logged a 6.9-percent growth, picking up the pace for the first time in seven years.