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of grant.The options outstanding under the Stock Plan expire at various dates through October 2012. 

In addition, the Stock Plan permits us to issue share awards to our employees and non-employee directors. A share award is an award of common stock, which (i) may be fully vested upon issuance or (ii) may be subject to the risk of forfeiture under Section 83 of the Internal Revenue Code. Shares issued generally vest over a one to three year period from the date of issuance and the sale of the shares is restricted prior to the date of vesting. During 2004, we awarded 130,143 shares of common stock.The unearned portion of these awards is amortized as stock compensation expense on a straight-line basis over the vesting period. 

The fair value of the options issued under the Stock Plan was estimated at the date of grant using a Black-Scholes option pricing model with the following weighted average assumptions for 2004, 2003 and 2002: 

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A summary of the stock option activity under our Stock Plan and related information for the years ended December 31, 2004, 2003 and 2002 follows: 

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The following table summarizes information about stock options outstanding at December 31, 2004: 

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