Real Estate (Tables)

3 Months Ended

Mar. 31, 2017

Investments in real estate properties consisted of the following (dollars and square feet in thousands):

	Square Feet				Number of Buildings
	March 31,		December 31,		March 31,		December 31,		March 31,		December 31,
	2017		2016		2017		2016		2017		2016
Operating properties
Buildings and improvements		329,743		331,210		1,762		1,776	$	17,911,386	$	17,905,914
Improved land										6,038,816		6,037,543
Development portfolio, including land costs:
Prestabilized		7,784		8,256		26		29		725,949		798,233
Properties under development		19,133		19,539		54		60		761,509		633,849
Land (1)										1,162,427		1,218,904
Other real estate investments (2)										531,142		524,887
Total investments in real estate properties										27,131,229		27,119,330
Less accumulated depreciation										3,914,817		3,758,372
Net investments in real estate properties									$	23,216,412	$	23,360,958

(1)	Included in our investments in real estate at March 31, 2017, and December 31, 2016, were 5,665 and 5,892 acres of land, respectively.

(2)

Included in other real estate investments are: (i) non-logistics real estate; (ii) land parcels that are ground leased to third parties; (iii) our corporate office buildings; (iv) costs related to future development projects, including purchase options on land; (v) infrastructure costs related to projects we are developing on behalf of others; and (vi) earnest money deposits associated with potential acquisitions.

Summary of Properties Disposed

The following table summarizes our real estate disposition activity for the three months ended March 31 (dollars and square feet in thousands):

	2017		2016
Contributions to unconsolidated co-investment ventures
Number of properties		5		5
Square feet		2,769		2,711
Net proceeds (1)	$	397,489	$	397,895
Net gains on contributions (1)	$	88,366	$	93,139
Dispositions to third parties
Number of properties		18		27
Square feet		2,318		2,244
Net proceeds (1) (2)	$	243,389	$	280,579
Net gains on dispositions (1) (2)	$	8,959	$	51,178

Total gains on dispositions of investments in real estate, net	$	97,325	$	144,317

(1)	Includes the contribution and disposition of land parcels.

(2)	Includes the sale of our investment in European Logistics Venture 1 (“ELV”) in 2017. See Note 3 for more information on this transaction.