U.S. corporate giants are the teeth of another wild ride on Wall Street as investors brace for the end of a week of historic losses for the Dow and other major indices.

The Dow was down 357 points, or 1.3%, at the close of trading Friday, after falling more than 1,000 points early on in the day. The NASDAQ was on a similar seesaw, falling by more than 200 points at the start of the day but closing with a gain of just under 1%.

AT&T, Apple, Comcast and Disney saw declines in the 3%-5% range in early trading on Friday as global markets react to spiking fears about the coronavirus crisis expanding rapidly into a full-fledged pandemic. By the end of the day, Apple and Disney were essentially flat while AT&T and Comcast were down about 1%.

The Dow Jones Industrial Average fell more than 1,000 points shortly after the session began. The NASDAQ sank more than 200 points. By 1 p.m. ET, both Dow and NASDAQ had recovered some, with the Dow hovering around a 400-point loss and NASDAQ about 40-50 points in the red. Major media and tech stocks made some strides in the afternoon, seesawing between losses in the 1%-2% range to slight gains.

The fast selloff on Thursday — when the Dow logged a new record for total point loss in a single day with a 1,190-point plunge, a 4.4% decline — was fueled by an ominous report from California that a woman there has been diagnosed with coronavirus but it is unclear how she contracted it, suggesting that more people in the region may have unknowingly been exposed to the potentially deadly disease.

Since Monday, the Dow has lost 13.4% of its value. Market watchers have been pointing to the opportunity for investors to go bargain shopping for shares amid the correction.

ViacomCBS shares have been battered in recent months and took another dive last week following a less-than-stellar earnings report for the newly combined company. As of Thursday, the stock has lost 43% of its value since the start of the year, thanks to the combination of a bearish response to its post-merger strategy and this week’s broader market rout.

Late last week, ViacomCBS chairman Shari Redstone voted with her pocketbook, spending nearly $1 million on Feb. 21 to acquire 35,000 shares of ViacomCBS Class B stock at a price of $28.44 and $29.27. ViacomCBS shares closed on Thursday at $23.89. On Friday, the stock seemingly had nowhere to go but up and managed to deliver a 5% gain by 1 p.m. ET despite the general downturn. ViacomCBS shares finished out the day up 3%, to $24.61.

ViacomCBS board member Barbara Byrne also spent $213,000 on Feb. 21 to buy 7,500 Class B shares in the company.

Two other industry stocks that were slammed earlier in the week — AMC Networks and Discovery — turned the tide a little bit on Friday with gains of 9.5% and 4.1%, respectively.