Please answer the given financial question based on the context.
Context: 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 , 2005 and that all dividends were reinvested . purchases of equity securities 2013 during 2010 , we repurchased 17556522 shares of our common stock at an average price of $ 75.51 . the following table presents common stock repurchases during each month for the fourth quarter of 2010 : period total number of shares purchased [a] average price paid per share total number of shares purchased as part of a publicly announced plan or program [b] maximum number of shares that may yet be purchased under the plan or program [b] .
|period|total number ofsharespurchased [a]|averageprice paidper share|total number of sharespurchased as part of apublicly announced planor program [b]|maximum number ofshares that may yetbe purchased under the planor program [b]|
|oct . 1 through oct . 31|725450|84.65|519554|17917736|
|nov . 1 through nov . 30|1205260|89.92|1106042|16811694|
|dec . 1 through dec . 31|1133106|92.59|875000|15936694|
|total|3063816|$ 89.66|2500596|n/a|
[a] total number of shares purchased during the quarter includes approximately 563220 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 may 1 , 2008 , our board of directors authorized us to repurchase up to 40 million shares of our common stock through march 31 , 2011 . 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 . on february 3 , 2011 , our board of directors authorized us to repurchase up to 40 million additional shares of our common stock under a new program effective from april 1 , 2011 through march 31 , 2014. .
Question: for the quarter ended december 312010 what was percent of the total number of shares attested to upc by employees to pay stock option exercise prices


Answer: The answer is:0.18383