INVESTMENTS

Fixed Maturity Investments Trading

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




	September 30, 2018		December 31, 2017
U.S. treasuries	$	3,117,911	$	3,168,763
Agencies	143,980		47,646
Municipal	7,061		509,802
Non-U.S. government (Sovereign debt)	254,169		287,660
Non-U.S. government-backed corporate	137,512		163,651
Corporate	2,448,795		2,063,459
Agency mortgage-backed	836,376		500,456
Non-agency mortgage-backed	289,649		300,331
Commercial mortgage-backed	257,434		202,062
Asset-backed	321,892		182,725
Total fixed maturity investments trading	$	7,814,779	$	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.




September 30, 2018	Amortized Cost		Fair Value
Due in less than one year	$	303,364	$	301,817
Due after one through five years	4,759,113		4,694,059
Due after five through ten years	1,029,502		1,020,157
Due after ten years	96,311		93,395
Mortgage-backed	1,390,933		1,383,459
Asset-backed	322,661		321,892
Total	$	7,901,884	$	7,814,779

Equity Investments Trading

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




	September 30, 2018		December 31, 2017
Financials	$	262,173	$	253,543
Communications and technology	60,235		49,526
Industrial, utilities and energy	34,755		34,325
Consumer	26,649		24,779
Healthcare	25,250		21,364
Basic materials	4,209		4,717
Total	$	413,271	$	388,254

Pledged Investments

At September 30, 2018, $5.1 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 - $4.4 billion). Of this amount, $1.9 billion is on deposit with, or in trust accounts for the benefit of, U.S. state regulatory authorities (December 31, 2017 - $1.7 billion).

Reverse Repurchase Agreements

At September 30, 2018, the Company held $92.0 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						Nine months ended
	September 30, 2018			September 30, 2017			September 30, 2018			September 30, 2017
Fixed maturity investments	$	55,725		$	45,305		$	151,784		$	133,080
Short term investments	9,403			2,771			22,340			7,476
Equity investments	903			930			3,091			2,630
Other investments
Private equity investments	8,723			6,371			12,149			20,784
Other	8,665			(11,491		)	27,346			(4,520		)
Cash and cash equivalents	1,104			352			2,708			836
	84,523			44,238			219,418			160,286
Investment expenses	(3,827		)	(3,981		)	(10,890		)	(11,541		)
Net investment income	$	80,696		$	40,257		$	208,528		$	148,745

Net Realized and Unrealized Gains (Losses) on Investments

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




	Three months ended						Nine months ended
	September 30, 2018			September 30, 2017			September 30, 2018			September 30, 2017
Gross realized gains	$	5,229		$	16,343		$	14,945		$	43,053
Gross realized losses	(15,327		)	(6,126		)	(67,699		)	(29,902		)
Net realized (losses) gains on fixed maturity investments	(10,098		)	10,217			(52,754		)	13,151
Net unrealized (losses) gains on fixed maturity investments trading	(8,730		)	5,545			(73,522		)	48,940
Net realized and unrealized gains (losses) on investments-related derivatives	2,563			(4,020		)	(763		)	(4,344		)
Net realized gains on equity investments trading sold during the period	21,259			13,675			21,841			49,736
Net unrealized gains on equity investments trading still held at reporting date	8,636			16,635			18,783			36,055
Net realized and unrealized gains on equity investments trading	29,895			30,310			40,624			85,791
Net realized and unrealized gains (losses) on investments	$	13,630		$	42,052		$	(86,415	)	$	143,538