The stock market's slide will become painfully clear to many ordinary investors when they get a look at their end-of-the-year retirement account statements that are in the mail this month. "I'm anxiously waiting and quite nervous," said Mary Enright, 41, a software tester in Sioux Falls, S.D., who expects her retirement nest egg, contained in a 401(k) account, to be off 15 percent. by The Associated Press