Deferred Acquisition Costs

12 Months Ended

Dec. 31, 2017

Deferred Acquisition Costs

Deferred Acquisition Costs

7. Deferred Acquisition Costs

        Acquisition costs deferred and amortized were as follows:

	For the year ended December 31,
	2017			2016			2015
	(in millions)
Balance at beginning of year	$	3,380.2		$	3,276.1		$	2,993.0
Costs deferred during the year		421.8			402.3			390.3
Amortized to expense during the year (1)		(234.6	)		(285.1	)		(270.8	)
Adjustment related to unrealized (gains) losses on available-for-sale securities and derivative instruments		(26.7	)		(13.1	)		164.5
Other		—			—			(0.9	)
Balance at end of year	$	3,540.7		$	3,380.2		$	3,276.1

(1)Includes adjustments for revisions to estimated gross profits.