The stock market plunged within the first hour of trading with investors offloading big cap stocks, but buying pressure on private banks helped slow the VN-Index’s descent throughout the day.

An overwhelming 251 stocks lost against 110 that gained on the Ho Chi Minh Stock Exchange (HoSE), Vietnam’s main bourse on which the VN-Index is based. Total trading volume was relatively low this session at VND4 trillion ($172 million), VND200 billion ($8.6 million) lower than last month’s average.

The VN30 for HoSE’s 30 biggest caps also fell 0.84 percent, with 22 stocks losing and 8 gaining. Nearly half the stocks that closed in red fell more than 2 percent this session.

Leading losses was POW of state-owned electricity firm PetroVietnam Power, plunging 6.9 percent, its floor price, ending a streak of seven consecutive gaining sessions.

It was followed by SAB of major brewer Sabeco, down 4.9 percent, BVH of insurance giant Bao Viet Group, 4.5 percent, and MWG of electronics retailer Mobile World, 2.8 percent.

Most stocks in the construction sector fared badly. ROS of real estate developer FLC Faros tumbled 6.4 percent, CTD of construction giant Coteccons fell 2.7 percent and NVL of real estate developer Novaland shed 0.8 percent. However, VHM of real estate developer Vinhomes, the biggest capped stock in the sector, surged 2 percent.

BID of BIDV and VCB of Vietcombank, two of Vietnam’s three biggest state-owned lenders by assets, fell 0.8 percent and 0.9 percent respectively, while MBB of state-owned mid-sized Military Bank dropped 0.6 percent.

Other major losers this session included MSN of food conglomerate Masan Group, down 2.6 percent, HPG of leading steelmaker Hoa Phat Group, down 2.3 percent, and VNM of dairy giant Vinamilk, down 1.4 percent.

In the opposite direction, HDB of private HDBank topped gains with 4.4 percent. TCB of private Techcombank added 1.2 percent, EIB of private Eximbank, 0.3 percent, and CTG of state-owned giant VietinBank, also 0.3 percent.

VRE of mall operator Vincom Retail, sister corporation to Vinhomes and a Vingroup subsidiary, added 1.5 percent. Despite both its subsidiaries VHM and VRE gaining, VIC of Vingroup edged down 0.1 percent.

Meanwhile, the HNX-Index for stocks on the Hanoi Stock Exchange, home to mid and small caps, fell 1.05 percent, and the UPCoM-Index for stocks on the Unlisted Public Companies Market shed 0.59 percent.

Foreign investors continued to be net sellers, albeit at a much lower amount compared to last week’s average of VND403 billion ($17.3 million) per session. Monday’s net sell came to VND127 billion ($5.5 million), with selling pressure mostly on STB of private Sacombank, which fell 1.3 percent, and SSI of brokerage Saigon Securities Inc., which dropped 2.3 percent.