China’s industrial companies’ profits dropped in April following a surge in the previous month, official data showed Monday, adding to concerns over the recovery of the country’s economic growth.

Profits of industrial enterprises dropped 3.7% year-on-year in April, significantly down from a 13.9% increase in March, according to data released by the National Bureau of Statistics (NBS).

The drop was partly due to the timing of the value-added tax cut at the start of April, which prompted firms to shift purchases earlier to March, Zhu Hong, a senior statistician at the NBS, said. Zhu said the drop was also caused by a high base of comparison last year.

Some sectors outperformed. In the first four months of 2019, profits in the natural gas and oil exploration sector grew 19.7% year-on-year, up 9.4 percentage points from profit growth over the first three months, and firms in the electrical machinery and equipment manufacturing sector saw profits rising 14.5%.

China’s major economic indicators for investment, retail and industrial output in April also showed growth falling from multi-month highs in March. 

Total industrial profits over the first four months decreased 3.4% year-on-year, compared to a 3.3% decrease over the first quarter.

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