5. Per Unit Data

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

	For the Year Ended December 31,
	2015		2014		2013
Net Income attributable to Unitholders — Basic and Diluted	$	2,131,139	$	1,643,783	$	1,537,348


Weighted Average Units Outstanding — Basic		362,244,154		363,475,504		362,355,581
Effect of stock options of Simon		—		—		50

Weighted Average Units Outstanding — Diluted		362,244,154		363,475,504		362,355,631

For the year ended December 31, 2015 and 2014, potentially dilutive securities include long-term incentive performance units, or LTIP units. No securities had a material dilutive effect for the years ended December 31, 2015 and 2014. The only securities that had a dilutive effect for the year ended December 31, 2013 were options of Simon.

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

	For the Year Ended December 31,
	2015			2014			2013
Total distributions paid per unit	$	6.05		$	5.15		$	4.65


Percent taxable as ordinary income		94.30	%		100.00	%		97.50	%
Percent taxable as long-term capital gains		5.70	%		0.00	%		2.50	%

		100.00	%		100.00	%		100.00	%

In January 2016, Simon's Board of Directors declared a quarterly cash dividend for the first quarter of 2016 of $1.60 per share. The distribution rate on our units is equal to the dividend rate on Simon's common stock.