american tower corporation and subsidiaries notes to consolidated financial statements 2014 ( continued ) sfas no . 148 . in accordance with apb no . 25 , the company recognizes compensation expense based on the excess , if any , of the quoted stock price at the grant date of the award or other measurement date over the amount an employee must pay to acquire the stock . the company 2019s stock option plans are more fully described in note 14 . in december 2004 , the fasb issued sfas no . 123 ( revised 2004 ) , 201cshare-based payment 201d ( sfas 123r ) , as further described below . during the year ended december 31 , 2005 , the company reevaluated the assumptions used to estimate the fair value of stock options issued to employees . as a result , the company lowered its expected volatility assumption for options granted after july 1 , 2005 to approximately 30% ( 30 % ) and increased the expected life of option grants to 6.25 years using the simplified method permitted by sec sab no . 107 , 201dshare-based payment 201d ( sab no . 107 ) . the company made this change based on a number of factors , including the company 2019s execution of its strategic plans to sell non-core businesses , reduce leverage and refinance its debt , and its recent merger with spectrasite , inc . ( see note 2. ) management had previously based its volatility assumptions on historical volatility since inception , which included periods when the company 2019s capital structure was more highly leveraged than current levels and expected levels for the foreseeable future . management 2019s estimate of future volatility is based on its consideration of all available information , including historical volatility , implied volatility of publicly traded options , the company 2019s current capital structure and its publicly announced future business plans . for comparative purposes , a 10% ( 10 % ) change in the volatility assumption would change pro forma stock option expense and pro forma net loss by approximately $ 0.1 million for the year ended december 31 , 2005 . ( see note 14. ) the following table illustrates the effect on net loss and net loss per common share if the company had applied the fair value recognition provisions of sfas no . 123 ( as amended ) to stock-based compensation . the estimated fair value of each option is calculated using the black-scholes option-pricing model ( in thousands , except per share amounts ) : .
what was the percentage decrease in the pro-forma net loss
the company has modified certain option awards to revise vesting and exercise terms for certain terminated employees and recognized charges of $ 7.0 million , $ 3.0 million and $ 2.3 million for the years ended december 31 , 2005 , 2004 and 2003 , respectively . in addition , the stock-based employee compensation amounts above for the year ended december 31 , 2005 , include approximately $ 2.4 million of unearned compensation amortization related to unvested stock options assumed in the merger with spectrasite , inc . such charges are reflected in impairments , net loss on sale of long-lived assets , restructuring and merger related expense with corresponding adjustments to additional paid-in capital and unearned compensation in the accompanying consolidated financial statements . recent accounting pronouncements 2014in december 2004 , the fasb issued sfas 123r , which supersedes apb no . 25 , and amends sfas no . 95 , 201cstatement of cash flows . 201d this statement addressed the accounting for share-based payments to employees , including grants of employee stock options . under the new standard .