5. Per Share Data

We determine basic earnings per share based on the weighted average number of shares of common stock outstanding during the period and we consider any participating securities for purposes of applying the two-class method. We determine diluted earnings per share based on the weighted average number of shares of common stock outstanding combined with the incremental weighted average shares that would have been outstanding assuming all dilutive potential securities were converted into common shares at the earliest date possible. The following table sets forth the computation of our basic and diluted earnings per share.

	For the Year Ended December 31,

	2013		2012		2011
Net Income available to Common Stockholders — Basic	$	1,316,304	$	1,431,159	$	1,021,462
Effect of dilutive securities:
Impact to General Partner's interest in Operating Partnership from all dilutive securities and options		—		—		39


Net Income available to Common Stockholders — Diluted	$	1,316,304	$	1,431,159	$	1,021,501




Weighted Average Shares Outstanding — Basic		310,255,168		303,137,350		293,504,064
Effect of stock options		50		1,072		69,408


Weighted Average Shares Outstanding — Diluted		310,255,218		303,138,422		293,573,472

For the year ended December 31, 2013, potentially dilutive securities include stock options, units that are exchangeable for common stock and long-term incentive performance, or LTIP, units granted under our long-term incentive performance programs that are convertible into units and exchangeable for common stock. The only securities that had a dilutive effect for the years ended December 31, 2013, 2012, and 2011 were stock options.

We accrue dividends when they are declared. The taxable nature of the dividends declared for each of the years ended as indicated is summarized as follows:

	For the Year Ended December 31,

	2013	2012	2011
Total dividends paid per common share	$4.65	$4.10	$3.50




Percent taxable as ordinary income	97.5%	99.50%	98.30%
Percent taxable as long-term capital gains	2.50%	0.50%	1.70%


	100.0%	100.0%	100.0%

In January 2014, our Board of Directors declared a cash dividend of $1.25 per share of common stock payable on February 28, 2014 to stockholders of record on February 14, 2014.