what the percent of the total number of shares purchased in the fourth quarter of 2007 that was attested to upc by employees to pay stock option exercise prices
five-year performance comparison 2013 the following graph provides an indicator of cumulative total shareholder returns for the corporation as compared to the peer group index ( described above ) , the dow jones , and the s&p 500 . the graph assumes that the value of the investment in the common stock of union pacific corporation and each index was $ 100 on december 31 , 2002 , and that all dividends were reinvested . comparison of five-year cumulative return 2002 2003 2004 2005 2006 2007 upc s&p 500 peer group dj trans purchases of equity securities 2013 during 2007 , we repurchased 13266070 shares of our common stock at an average price of $ 115.66 . during the first nine months of 2007 , we repurchased 10639916 shares of our common stock at an average price per share of $ 112.68 . the following table presents common stock repurchases during each month for the fourth quarter of 2007 : period number of shares purchased average paid per total number of shares purchased as part of a publicly announced plan or program maximum number of shares that may yet be purchased under the plan or program .

| <i>Period</i> | <i>TotalNumber ofSharesPurchased[a]</i> | <i>AveragePricePaid perShare</i> | <i>Total Number of SharesPurchased as Part of aPublicly AnnouncedPlan orProgram</i> | <i>Maximum Number ofShares That May YetBe Purchased Underthe Plan orProgram[b]</i> |
| :--- | :--- | :--- | :--- | :--- |
| Oct. 1 through Oct. 31 | 99,782 | $ 128.78 | - | 9,774,279 |
| Nov. 1 through Nov. 30 | 540,294 | 124.70 | 528,000 | 9,246,279 |
| Dec. 1 through Dec. 31 | 1,986,078 | 128.53 | 1,869,800 | 7,376,479 |
| Total | 2,626,154 | $ 127.75 | 2,397,800 | N/A |

[a] total number of shares purchased during the quarter includes 228354 shares delivered or attested to upc by employees to pay stock option exercise prices , satisfy excess tax withholding obligations for stock option exercises or vesting of retention units , and pay withholding obligations for vesting of retention shares . [b] on january 30 , 2007 , our board of directors authorized us to repurchase up to 20 million shares of our common stock through december 31 , 2009 . we may make these repurchases on the open market or through other transactions . our management has sole discretion with respect to determining the timing and amount of these transactions. .

shares_repurchased = 228354
shares_total = 2626154
percent_attested = shares_repurchased / shares_total
answer = percent_attested * 100