3. Investments

The Company is a partner with Mitsui & Co., Ltd. in a joint venture based in Dublin, Ireland — Willis Mitsui & Company Engine Support Limited (“WMES”) which acquires and leases jet engines. Each partner holds a fifty percent interest in the joint venture and the Company uses the equity method in recording investment activity. WMES owned a lease portfolio of 34 engines and one aircraft with a net book value of $268.5 million as of March 31, 2018.

The Company is a partner with China Aviation Supplies Company Ltd. (“CASC”) in a joint venture named CASC Willis Engine Lease Company Limited (“CASC Willis”), which is based in Shanghai, China. The Company holds a fifty percent interest in the joint venture and uses the equity method in recording investment activity. CASC Willis acquires and leases jet engines to Chinese airlines and concentrates on the demand for leased commercial aircraft engines and aviation assets in the People’s Republic of China. CASC Willis owned a lease portfolio of 4 engines with a net book value of $58.8 million as of March 31, 2018.


Three Months Ended March 31, 2018	WMES		CASC Willis		Total
	(in thousands)
Investment in joint ventures as of December 31, 2017	$	36,014	$	14,627	$	50,641
Earnings from joint venture		390		357		747
Deferred gain on engine sale		(723)		—		(723)
Foreign Currency Translation Adjustment		—		585		585
Investment in joint ventures as of March 31, 2018	$	35,681	$	15,569	$	51,250

“Other revenue” on the Consolidated Statement of Income includes management fees earned of $0.7 million and $0.8 million during the three months ended March 31, 2018 and 2017, respectively, related to the servicing of engines for the WMES lease portfolio.

Summarized financial information for 100% of WMES is presented in the following tables:


	Three Months Ended March 31,
	2018		2017
	(in thousands)
Revenue	$	7,606	$	11,661
Expenses		6,904		8,430
WMES income before income taxes	$	702	$	3,231

	March 31,			December 31,
	2018			2017
	(in thousands)
Total assets	$	273,952	$	246,309
Total liabilities		192,169		165,228
Total WMES net equity	$	81,783	$	81,081