SAIC Motor Corp., the biggest auto company on China’s A-share market, reported flagging sales during the first four months of the year.

Auto sales plunged 16.8 percent year on year to 1.99 million units during the period, according to a statement filed to the Shanghai Stock Exchange.

Its three joint ventures, namely, SAIC Volkswagen, SAIC-GM and Shanghai General Motors Wuling, all witnessed falling sales, down 9.2 percent, 16.6 percent and 26.5 percent, respectively.

Its self-owned brands — Morris Garages and Roewe — were not spared from the sales slump, showing a 15.3-percent decline in sales during the period.

China, the world’s biggest auto market, has seen weak sales in recent months.

The country’s auto sales fell for the ninth straight month in March, but the contraction was smaller than that in January and February, data from the China Association of Auto Manufacturers showed.