HANOI, Nov 8 (Reuters) - Vietnam stocks extended falls for a fourth straight day on Tuesday to hit the lowest levels since November 2020, with the country's biggest conglomerate Vingroup leading the decline.

The benchmark stock index, which has plunged nearly 35% this year, is heading for its worst annual performance since the 2008 financial crisis.

By midday, the index dropped 1.35% to 962, the lowest level since late 2020. Vietnam's biggest conglomerate Vingroup led the fall, falling 6.7%, followed by its property unit Vinhomes with a 5.2% decrease.

"The real estate sector still has the worst performance," said a Hanoi-based trader at security firm VNDirect.

"That some real estate firms and bosses have been forced to sell their shares has caused a continuous fall in the market and affected investor sentiment."

A broker at Vietcombank Securities said gloomy economic outlooks and volatile markets around the world have made local retail investors reluctant to buy. (Reporting by Phuong Nguyen, Editing by Kanupriya Kapoor)