stock-based awards under the plan stock options 2013 marathon grants stock options under the 2007 plan and previously granted options under the 2003 plan .marathon 2019s stock options represent the right to purchase shares of common stock at the fair market value of the common stock on the date of grant .through 2004 , certain stock options were granted under the 2003 plan with a tandem stock appreciation right , which allows the recipient to instead elect to receive cash and/or common stock equal to the excess of the fair market value of shares of common stock , as determined in accordance with the 2003 plan , over the option price of the shares .in general , stock options granted under the 2007 plan and the 2003 plan vest ratably over a three-year period and have a maximum term of ten years from the date they are granted .stock appreciation rights 2013 prior to 2005 , marathon granted sars under the 2003 plan .no stock appreciation rights have been granted under the 2007 plan .similar to stock options , stock appreciation rights represent the right to receive a payment equal to the excess of the fair market value of shares of common stock on the date the right is exercised over the grant price .under the 2003 plan , certain sars were granted as stock-settled sars and others were granted in tandem with stock options .in general , sars granted under the 2003 plan vest ratably over a three-year period and have a maximum term of ten years from the date they are granted .stock-based performance awards 2013 prior to 2005 , marathon granted stock-based performance awards under the 2003 plan .no stock-based performance awards have been granted under the 2007 plan .beginning in 2005 , marathon discontinued granting stock-based performance awards and instead now grants cash-settled performance units to officers .all stock-based performance awards granted under the 2003 plan have either vested or been forfeited .as a result , there are no outstanding stock-based performance awards .restricted stock 2013 marathon grants restricted stock and restricted stock units under the 2007 plan and previously granted such awards under the 2003 plan .in 2005 , the compensation committee began granting time-based restricted stock to certain u.s.-based officers of marathon and its consolidated subsidiaries as part of their annual long-term incentive package .the restricted stock awards to officers vest three years from the date of grant , contingent on the recipient 2019s continued employment .marathon also grants restricted stock to certain non-officer employees and restricted stock units to certain international employees ( 201crestricted stock awards 201d ) , based on their performance within certain guidelines and for retention purposes .the restricted stock awards to non-officers generally vest in one-third increments over a three-year period , contingent on the recipient 2019s continued employment .prior to vesting , all restricted stock recipients have the right to vote such stock and receive dividends thereon .the non-vested shares are not transferable and are held by marathon 2019s transfer agent .common stock units 2013 marathon maintains an equity compensation program for its non-employee directors under the 2007 plan and previously maintained such a program under the 2003 plan .all non-employee directors other than the chairman receive annual grants of common stock units , and they are required to hold those units until they leave the board of directors .when dividends are paid on marathon common stock , directors receive dividend equivalents in the form of additional common stock units .stock-based compensation expense 2013 total employee stock-based compensation expense was $ 80 million , $ 83 million and $ 111 million in 2007 , 2006 and 2005 .the total related income tax benefits were $ 29 million , $ 31 million and $ 39 million .in 2007 and 2006 , cash received upon exercise of stock option awards was $ 27 million and $ 50 million .tax benefits realized for deductions during 2007 and 2006 that were in excess of the stock-based compensation expense recorded for options exercised and other stock-based awards vested during the period totaled $ 30 million and $ 36 million .cash settlements of stock option awards totaled $ 1 million and $ 3 million in 2007 and 2006 .stock option awards granted 2013 during 2007 , 2006 and 2005 , marathon granted stock option awards to both officer and non-officer employees .the weighted average grant date fair value of these awards was based on the following black-scholes assumptions: .
[['', '2007', '2006', '2005'], ['weighted average exercise price per share', '$ 60.94', '$ 37.84', '$ 25.14'], ['expected annual dividends per share', '$ 0.96', '$ 0.80', '$ 0.66'], ['expected life in years', '5.0', '5.1', '5.5'], ['expected volatility', '27% ( 27 % )', '28% ( 28 % )', '28% ( 28 % )'], ['risk-free interest rate', '4.1% ( 4.1 % )', '5.0% ( 5.0 % )', '3.8% ( 3.8 % )'], ['weighted average grant date fair value of stock option awards granted', '$ 17.24', '$ 10.19', '$ 6.15']]
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Question: by how much did the expected annual dividends per share increase from 2005 to 2007?
Answer: 45.5%