China’s major industrial firms posted steady profit growth in the first half of the year, further evidence of firming strength in the economy, official data showed on Thursday.

The National Bureau of Statistics reported that industrial profits increased 22 percent in the first six months of 2017 year on year. It was much quicker than the 6.2-percent increase in the same period last year. Profits of major industrial companies rose 19.1 percent year on year in June alone, faster than the 16.7-percent rate in May.

Analysts said the growth was partly boosted by stronger sales and increased return on investments by companies.

"The growth of industrial profits was mainly driven by price fluctuations in raw materials. For other industries, the growth of industrial profits was relatively moderate," said Jiang Feitao, a researcher at Chinese Academy of Social Sciences.