NEW YORK (TheStreet) -- BlackBerry (BBRY - Get Report) and Plug Power (PLUG - Get Report) have plunged on a day already a hard slog for stocks. By early afternoon, BlackBerry had taken off 4.9% to $8.98, while Plug Power was down 5.6% to $2.85. Neither company had released news, but susceptibility to selling-off on market tremors likely contributed to a larger-than-normal drop.
The S&P 500 had sunk 1.68% to 1,752.71 by Monday afternoon on the release of weak U.S. manufacturing data and poor auto sales.
Earlier in the day, the Institute for Supply Management said manufacturing growth in the U.S. over January had dropped to 51.3 from 56.5 in December, an eight-month low. New order growth fell by the most in 33 years to 51.2 from 64.4.
Adding to concerns of a weakening national economy, Ford (F) and General Motors (GM) reported worse-than-expected auto sales over January. Ford said unit sales plummeted 7.1% to 154,000, while General Motors' unit sales sunk 12% to 171,000. The automakers blamed wintery weather and icy conditions over the last month for a lack of customers.Prior to Monday, BlackBerry had climbed 27% since the beginning of the year as investors gained confidence a turnaround could take root under new CEO John Chen's direction. Meanwhile, Plug Power was up 94.8% year to date after announcing contracts from Wal-Mart (WMT), Kroger (KR), Coca-Cola (KO) and Procter & Gamble (PG), as well as a new public offering of 10 million shares earlier in January.