BEIJING - China's major industrial firms posted steady profit growth in the first seven months of the year, official data showed Sunday.

From January to July, industrial companies with annual revenue over 20 million yuan (about $3 million) reported total profits of more than 4.2 trillion yuan, 21.2 percent more than the same period in 2016, the National Bureau of Statistics (NBS) said in a statement.

The growth rate was slightly slower than the 22 percent in January-June but much faster than the 8.5 percent increase in 2016.

In July, profits of major industrial firms rose 16.5 percent year on year, slower than the 19.1 percent rate in June.

NBS statistician He Ping attributed the slower growth in profit to high temperatures in July when a number of factories halted production.

However, industrial performance has kept improving and has profit maintained fast growth thanks to ongoing supply-side structural reform, He added.

From January to July, profit in the equipment manufacturing sector surged 18.1 percent year on year to over 3.7 trillion yuan, and in the mining industry jumped 790 percent to 279.6 billion yuan.

The industrial sector, which accounts for about one-third of China's GDP, started to pick up last year after a bad 2015.

There are also signs pointing to a stabilizing industrial sector.

In July, the costs of major industrial firms went down, He said. For each 100 yuan of revenue, companies had to spend 93.12 yuan, compared to 93.41 yuan for the same period last year, NBS data showed.

The companies also reported healthier balance sheets. The average collection period for accounts receivable decreased from 38.1 days a year earlier to 37.1 days by the end of July.

The corporate leverage ratio continue to decline. Debt-asset ratios of major industrial firms dropped 0.7 percentage points year on year to 55.8 percent by the end of July.

In the meantime, the profit rate of major industrial companies rose by 0.33 percentage points to 5.97 percent in July.

The NBS statistician also highlighted the strong performance of state owned major industrial companies whose profit surged 34.2 percent in July year on year. In June, their profit increased 20.7 percent, the NBS said.

The new data is the latest in a slew of economic indicators that showed China's economy is steadily stabilizing and improving, prompting global institutions such as the IMF to raise GDP forecasts for the country.

China's economy expanded 6.9 percent for the first half of 2017, with consumption and services, together with new innovation-driven economic sectors, taking up larger roles in the economy.

In light of the strong data and expectations of continued fiscal support, the IMF in July revised up China's growth forecast for 2017 and 2018 to 6.7 percent and 6.4 percent respectively.