Business Segments

During the year ended December 31, 2017, we revised the information regularly reviewed by our chief executive officer, who is our chief operating decision maker, to assess our operating performance. Apartment communities are classified as either part of our Real Estate portfolio or as those owned by partnerships served by our Asset Management business.

Our chief operating decision maker uses proportionate property net operating income to assess the operating performance of our apartment communities. Proportionate property net operating income reflects our share of rental and other property revenues less direct property operating expenses, including real estate taxes, for consolidated apartment communities we own and manage. As of December 31, 2017, for segment performance evaluation, our Real Estate segment included 132 consolidated apartment communities with 36,762 apartment homes and excluded four apartment communities with 142 apartment homes that we neither manage nor consolidate.

As of December 31, 2017, through our Asset Management business we also held nominal ownership positions in consolidated partnerships that own 46 low-income housing tax credit apartment communities with 6,898 apartment homes. Neither the results of operations nor the assets of these partnerships and apartment communities are quantitatively material; therefore, we have one reportable segment, Real Estate. The results of operations for the years ended December 31, 2016 and 2015, and the segment assets as of December 31, 2016, shown below have been revised to reflect the change in our reportable segments.

The following tables present the revenues, net operating income and income before gain on dispositions of our Real Estate segment on a proportionate basis (excluding amounts related to apartment communities sold or classified as held for sale as of December 31, 2017) for the years ended December 31, 2017, 2016 and 2015 (in thousands):



	Real Estate		Proportionate Adjustments (1)		Corporate and Amounts Not Allocated to Reportable Segment (2)			Consolidated
Year Ended December 31, 2017:
Rental and other property revenues attributable to Real Estate	$	854,491	$	15,481	$	48,176		$	918,148
Rental and other property revenues of partnerships served by Asset Management business	—		—		74,046			74,046
Tax credit and transaction revenues	—		—		13,243			13,243
Total revenues	854,491		15,481		135,465			1,005,437
Property operating expenses attributable to Real Estate	265,186		4,887		48,866			318,939
Property operating expenses of partnerships served by Asset Management business	—		—		35,440			35,440
Other operating expenses not allocated to reportable segment (3)	—		—		457,075			457,075
Total operating expenses	265,186		4,887		541,381			811,454
Operating income	589,305		10,594		(405,916		)	193,983
Other items included in income before gain on dispositions (4)	—		—		(146,463		)	(146,463		)
Income before gain on dispositions	$	589,305	$	10,594	$	(552,379	)	$	47,520



	Real Estate		Proportionate Adjustments (1)		Corporate and Amounts Not Allocated to Reportable Segment (2)			Consolidated
Year Ended December 31, 2016:
Rental and other property revenues attributable to Real Estate	$	791,587	$	28,509	$	79,795		$	899,891
Rental and other property revenues of partnerships served by Asset Management business	—		—		74,640			74,640
Tax credit and transaction revenues	—		—		21,323			21,323
Total revenues	791,587		28,509		175,758			995,854
Property operating expenses attributable to Real Estate	251,636		8,284		58,037			317,957
Property operating expenses of partnerships served by Asset Management business	—		—		36,956			36,956
Other operating expenses not allocated to reportable segment (3)	—		—		394,145			394,145
Total operating expenses	251,636		8,284		489,138			749,058
Operating income	539,951		20,225		(313,380		)	246,796
Other items included in income before gain on dispositions (4)	—		—		(157,313		)	(157,313		)
Income before gain on dispositions	$	539,951	$	20,225	$	(470,693	)	$	89,483



	Real Estate		Proportionate Adjustments (1)		Corporate and Amounts Not Allocated to Reportable Segment (2)			Consolidated
Year Ended December 31, 2015:
Rental and other property revenues attributable to Real Estate	$	737,079	$	28,875	$	117,066		$	883,020
Rental and other property revenues of partnerships served by Asset Management business	—		—		73,934			73,934
Tax credit and transaction revenues	—		—		24,356			24,356
Total revenues	737,079		28,875		215,356			981,310
Property operating expenses attributable to Real Estate	240,789		8,857		74,933			324,579
Property operating expenses of partnerships served by Asset Management business	—		—		37,537			37,537
Other operating expenses not allocated to reportable segment (3)	—		—		362,979			362,979
Total operating expenses	240,789		8,857		475,449			725,095
Operating income	496,290		20,018		(260,093		)	256,215
Other items included in income before gain on dispositions (4)	—		—		(164,825		)	(164,825		)
Income before gain on dispositions	$	496,290	$	20,018	$	(424,918	)	$	91,390


(1)	Represents adjustments for the noncontrolling interests in consolidated real estate partnerships’ share of the results of consolidated apartment communities in our Real Estate segment, which are included in the related consolidated amounts, but excluded from proportionate property net operating income for our segment evaluation.

(2)

Includes the operating results of apartment communities sold during the periods shown or held for sale at the end of the period, if any, and the operating results of apartment communities owned by consolidated partnerships served by our Asset Management business. Corporate and Amounts Not Allocated to Reportable Segment also includes property management expenses and casualty gains and losses (which are included in consolidated property operating expenses), which are property related items that are not part of our segment performance measure.


(3)	Other operating expenses not allocated to reportable segment consists of depreciation and amortization, general and administrative expenses and other operating expenses including provision for real estate impairment loss, which are not included in our measure of segment performance.


(4)	Other items included in income before gain on dispositions primarily consist of interest expense and income tax benefit.

The assets of our reportable segment and the consolidated assets not allocated to our segment are as follows (in thousands):



	December 31,
	2017		2016
Real Estate	$	5,495,069	$	5,432,642
Corporate and other assets (1)	583,971		800,176
Total consolidated assets	$	6,079,040	$	6,232,818


(1)	Includes the assets of consolidated partnerships served by the Asset Management business and apartment communities sold or classified as held for sale as of December 31, 2017.

For the years ended December 31, 2017, 2016 and 2015, capital additions related to our Real Estate segment totaled $338.0 million, $321.0 million and $340.3 million, respectively.