Investors who weren't already superstitious after suffering a year of brutal markets had good reason to believe in voodoo this month. The Morningstar Web site, which is widely used by investors to pick funds, was grossly inaccurate on, of all days, Friday the 13th.

Chicago-based Morningstar said last week that a software glitch caused the company's Web site to display incorrect data for all of the 14,000 funds that the firm reviews. The erroneous numbers were posted at Morningstar.com for less than 12 hours on Sept. 13, said spokeswoman Kathy Habiger.

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