Property, net:

Property at December 31, 2016 and 2015 consists of the following:



	2016			2015
Land	$	1,607,590		$	1,894,717
Buildings and improvements	6,511,741			7,752,892
Tenant improvements	622,878			637,355
Equipment and furnishings	177,036			169,841
Construction in progress	289,966			234,851
	9,209,211			10,689,656
Less accumulated depreciation	(1,851,901		)	(1,892,744		)
	$	7,357,310		$	8,796,912

Depreciation expense for the years ended December 31, 2016, 2015 and 2014 was $277,270, $354,977 and $289,178, respectively.

The gain on sale or write down of assets, net for the year ended December 31, 2016 includes a gain of $101,629 on the sale of a 40% ownership interest in Arrowhead Towne Center (See Note 4—Investments in Unconsolidated Joint Ventures), $340,734 on the sale of a 49% ownership interest in the MAC Heitman Portfolio (See Note 4—Investments in Unconsolidated Joint Ventures), $24,894 on the sale of Capitola Mall (See Note 14—Dispositions) and $4,546 on the sale of land. These gains were offset in part by a loss of $39,671 on impairment, a charge of $12,180 from a contingent consideration obligation, a loss of $3,066 on the sale of a former Mervyn's store (See Note 14—Dispositions) and $1,538 on the write-off of development costs. The loss on impairment was due to the reduction of the estimated holding periods of Cascade Mall (See Note 22—Subsequent Events), Promenade at Casa Grande, The Marketplace at Flagstaff and a freestanding store.

The gain on sale or write down of assets, net for the year ended December 31, 2015 includes the gain of $311,194 on the sale of a 40% ownership interest in the PPR Portfolio (See Note 4—Investments in Unconsolidated Joint Ventures), $73,726 on the sale of Panorama Mall (See Note 14—Dispositions), $2,336 on the sale of assets and $1,807 on the sale of land offset in part by a loss of $10,633 on impairment and $182 on the write-off of development costs. The loss on impairment was due to the reduction of the estimated holding periods of Flagstaff Mall (See Note 14—Dispositions) and a freestanding store.

The gain on sale or write down of assets, net for the year ended December 31, 2014 includes the gain of $144,927 on the sales of Rotterdam Square, Somersville Towne Center, Lake Square Mall, South Towne Center, Camelback Colonnade and four former Mervyn's stores (See Note 14—Dispositions), $9,033 on the sale of Wilshire Boulevard (See Note 4—Investments in Unconsolidated Joint Ventures) and $1,257 on the sale of assets offset in part by a loss of $41,216 on impairment and $40,561 on the write-off of development costs. The loss on impairment was due to the reduction in the estimated holding periods of the long-lived assets of several properties including Great Northern Mall, Cascade Mall, a property adjacent to Fiesta Mall and three former Mervyn's stores sold in 2014 (See Note 14—Dispositions).

The following table summarizes certain of the Company's assets that were measured on a nonrecurring basis as a result of impairment charges recorded for the years ended December 31, 2016, 2015 and 2014 as described above:



Years ended December, 31	Total Fair Value Measurement		Quoted Prices in Active Markets for Identical Assets		Significant Other Unobservable Inputs		Significant Unobservable Inputs
Years ended December, 31	Total Fair Value Measurement		(Level 1)		(Level 2)		(Level 3)
2016	$	86,100	$	—	$	—	$	86,100
2015	$	33,300	$	—	$	—	$	33,300
2014	$	44,500	$	—	$	—	$	44,500

The fair value relating to impairment assessments were based upon a discounted cash flow model that includes all cash inflows and outflows over a specific holding period. Such projected cash flows are comprised of contractual rental revenues and forecasted rental revenues and expenses based upon market conditions and expectations for growth. Terminal capitalization rates and discount rates utilized in these models are based on a reasonable range of current market rates for each property analyzed. Based upon these inputs, the Company determined that its valuations of properties using a discounted cash flow model are classified within Level 3 of the fair value hierarchy.

The following table sets forth quantitative information about the unobservable inputs of the Company’s Level 3 real estate recorded as of December 31, 2016, 2015 and 2014:



Unobservable Inputs	2016	2015	2014
Terminal capitalization rate	7.0% - 10.0%	9.0%	8.0% - 9.0%
Discount rate	8.0% - 15.0%	9.5%	9.0% - 10.5%
Market rents per square foot	$2.00 - $20.00	$5.00 - $150.00	$6.00 - $160.00