The Company, as an owner of real estate, is subject to various Federal, state and local environmental laws. Compliance by the Company with existing laws has not had a material adverse effect on the Company. However, the Company cannot predict the impact of new or changed laws or regulations on its current properties or on properties that it may acquire in the future. As of December 31, 2018, the Company does have environmental reserves totaling approximately $4.5 million related to three of its properties.

The Company had established a reserve related to various litigation matters associated with its Massachusetts properties and periodically assessed the adequacy of the reserve and made adjustments as necessary. As of December 31, 2018, the matters were resolved for a total payout of $0.9 million and no reserve remains outstanding.

The Company does not believe there is any litigation pending or threatened against it that, individually or in the aggregate, may reasonably be expected to have a material adverse effect on the Company.

As of December 31, 2018, the Company has three wholly owned projects totaling 690 apartment units in various stages of development with remaining commitments to fund of approximately $414.1 million and estimated completion dates ranging through September 30, 2021, as well as other completed development projects that are in various stages of lease-up or are stabilized.

As of December 31, 2018, the Company has two unconsolidated operating properties that are owned with the same third party joint venture partner under separate agreements. The joint venture agreements with this partner are primarily deal-specific regarding profit-sharing, equity contributions, returns on investment, buy-sell agreements and other customary provisions. The buy-sell arrangements contain provisions that provide the right, but not the obligation, for the Company to acquire the partner’s interests or sell its interests at any time following the occurrence of certain pre-defined events described in the joint venture agreements.

During the years ended December 31, 2018, 2017 and 2016, total operating lease expense for ground leases and office space, including a portion of real estate taxes, insurance, repairs and utilities, aggregated $27.8 million, $26.6 million and $26.2 million, respectively.

The Company has entered into a retirement benefits agreement with its Chairman of the Board of Trustees and deferred compensation agreements with its Vice Chairman and one former chief executive officer. During the years ended December 31, 2018, 2017 and 2016, the Company recognized compensation expense of $0.3 million, $0.4 million and $0.3 million, respectively, related to these agreements.

The following table summarizes the Company’s contractual obligations for minimum rent payments under operating leases and deferred compensation for the next five years and thereafter as of December 31, 2018:

(Payments)/Receipts Due by Year (in thousands)
	2019			2020			2021			2022			2023			Thereafter			Total
Operating Leases:
Minimum Rent Payments (a)	$	(16,718	)	$	(16,726	)	$	(16,665	)	$	(14,500	)	$	(14,339	)	$	(953,001	)	$	(1,031,949	)
Minimum Rent Receipts (b)	$	64,790		$	61,409		$	57,326		$	53,193		$	46,016		$	172,694		$	455,428
Other Long-Term Liabilities:
Deferred Compensation (c)	$	(803	)	$	(1,100	)	$	(1,100	)	$	(1,100	)	$	(975	)	$	(3,810	)	$	(8,888	)

(a)	Minimum basic rent due for various office space the Company leases and fixed base rent due on ground leases for 12 properties.

(b)	Minimum basic rent receipts due for various retail/commercial space where the Company is the lessor.

(c)	Estimated payments to the Company’s Chairman, Vice Chairman and one former CEO based on actual and estimated retirement dates.