Updated from 8:58 a.m. ESTStocks in New York opened on the downside Monday, as investors took profits from the previous week's gains and major firms across sectors undertook restructuring measures amid a weakening economic environment. The Dow Jones Industrial Average slid 213 points to 8616, and the S&P 500 fell 24 points to 872. The Nasdaq was lower by 42 at 1493. At the end of an abbreviated session Friday, the major averages finished on the upside in light trading. Investors were monitoring the retailers as consumers flocked to stores to partake in "Black Friday" sales, which mark the beginning of the holiday shopping season. Today marks "Cyber Monday," when online retailers compete for Internet sales by offering steep discounts through their Web sites. Last week, the S&P 500 rose 12%, while Nasdaq gained 11%. Ahead of Monday's trading, beleaguered automaker General Motors ( GM) was ironing out a plan to cajole Congress into giving it federal money, according to a report by The Wall Street Journal. The report indicated that GM's board is willing to explore all restructuring options, including a Chapter 11 bankruptcy filing, if it can't secure government funds. Over the weekend, another report by the Journal said that GM was exploring other plans to shore up its balance sheet, including offering its debt holders the opportunity to swap credit for equity. As the carmakers faced dire circumstances, the United Auto Workers called for Congressional aid for the Big Three. The Journal also reported that Delta Air Lines ( DAL) would scale back its orders for Boeing's ( BA) new 787 Dreamliner and instead add to its orders for the long-range 777-200LR.