INVESTMENTS

Fixed Maturity Investments Trading

The following table summarizes the fair value of fixed maturity investments trading:




	March 31, 2018		December 31, 2017
U.S. treasuries	$	2,834,487	$	3,168,763
Agencies	45,365		47,646
Municipal	506,470		509,802
Non-U.S. government (Sovereign debt)	303,056		287,660
Non-U.S. government-backed corporate	191,202		163,651
Corporate	2,147,578		2,063,459
Agency mortgage-backed	693,377		500,456
Non-agency mortgage-backed	302,638		300,331
Commercial mortgage-backed	197,126		202,062
Asset-backed	183,462		182,725
Total fixed maturity investments trading	$	7,404,761	$	7,426,555

Contractual maturities of fixed maturity investments trading are described in the following table. Expected maturities will differ from contractual maturities because borrowers may have the right to call or prepay obligations with or without call or prepayment penalties.




March 31, 2018	Amortized Cost		Fair Value
Due in less than one year	$	496,788	$	495,143
Due after one through five years	4,381,056		4,324,744
Due after five through ten years	1,073,453		1,064,575
Due after ten years	145,438		143,696
Mortgage-backed	1,189,730		1,193,141
Asset-backed	183,538		183,462
Total	$	7,470,003	$	7,404,761

Equity Investments Trading

The following table summarizes the fair value of equity investments trading:




	March 31, 2018		December 31, 2017
Financials	$	253,905	$	253,543
Communications and technology	51,400		49,526
Industrial, utilities and energy	32,790		34,325
Consumer	23,886		24,779
Healthcare	21,042		21,364
Basic materials	4,439		4,717
Total	$	387,462	$	388,254

Pledged Investments

At March 31, 2018, $4.7 billion of cash and investments at fair value were on deposit with, or in trust accounts for the benefit of, various counterparties, including with respect to the Company’s letter of credit facilities (December 31, 2017 - $3.3 billion). Of this amount, $1.7 billion is on deposit with, or in trust accounts for the benefit of, U.S. state regulatory authorities (December 31, 2017 - $1.4 billion).

Reverse Repurchase Agreements

At March 31, 2018, the Company held $65.3 million (December 31, 2017 - $30.0 million) of reverse repurchase agreements. These loans are fully collateralized, are generally outstanding for a short period of time and are presented on a gross basis as part of short term investments on the Company’s consolidated balance sheets. The required collateral for these loans typically includes high-quality, readily marketable instruments at a minimum amount of 102% of the loan principal. Upon maturity, the Company receives principal and interest income.

Net Investment Income

The components of net investment income are as follows:




	Three months ended
	March 31, 2018			March 31, 2017
Fixed maturity investments	$	45,643		$	43,419
Short term investments	5,304			1,724
Equity investments	698			811
Other investments
Private equity investments	(434		)	7,802
Other	8,023			4,072
Cash and cash equivalents	565			189
	59,799			58,017
Investment expenses	(3,323		)	(3,692		)
Net investment income	$	56,476		$	54,325

Net Realized and Unrealized (Losses) Gains on Investments

Net realized and unrealized (losses) gains on investments are as follows:




	Three months ended
	March 31, 2018			March 31, 2017
Gross realized gains	$	4,583		$	11,461
Gross realized losses	(25,853		)	(16,533		)
Net realized losses on fixed maturity investments	(21,270		)	(5,072		)
Net unrealized (losses) gains on fixed maturity investments trading	(55,372		)	24,635
Net realized and unrealized losses on investments-related derivatives	(4,364		)	(56		)
Net realized gains on equity investments trading sold during the period	234			20,915
Net unrealized (losses) gains on equity investments trading still held at reporting date	(1,372		)	2,951
Net realized and unrealized (losses) gains on equity investments trading	(1,138		)	23,866
Net realized and unrealized (losses) gains on investments	$	(82,144	)	$	43,373