[in thousands of Canadian dollars, except per share amounts] December 31, 2012 and 2011 [C] BASIC AND DILUTED EARNINGS PER SHARE The following table presents the calculation of basic and diluted earnings per common share for the years ended  December 31: [in thousands] 2012 2011 Numerator: Net income – basic and diluted  $352,163  $376,899 Denominator: Weighted average number of common shares – basic  283,390 286,998 Weighted average effect of dilutive stock options (*)  640 1,202 Weighted average number of common shares – diluted  284,030 288,200 Net earnings per common share Basic $1.24 $1.31 Diluted $1.24 $1.31 (*) The determination of the weighted average number of common shares – diluted excludes nil shares related to stock options that  were anti-dilutive for the year ended December 31, 2012 [and 3,393 thousand shares for the year ended December 31, 2011]. [D] MAXIMUM SHARE DILUTION The following table presents the maximum number of shares that would be outstanding if all the outstanding options as  at January 31, 2013 were exercised and outstanding: [in thousands]  Shares outstanding at January 31, 2013  283,193 Options to purchase shares  5,029 288,222 72 Notes to Consolidated Financial Statements