The dispersion is somewhat larger when measuring average annual returns (annualized return, recall, is the compounded or geometric rate of return during a multiple-year time period).

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On Jan. 18 Nortel was trading at 58 times 2001 estimated earnings, while Lucent's multiple was 25 for the same time period.

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Users can practice this with, for instance, leaving the house without checking the door lock multiple times, over a given time period.

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