Favorable and Unfavorable Acquired Lease Contracts, net

Favorable and unfavorable acquired lease contracts represent the acquired fair value of lease contracts in connection with the Central Merger. Favorable and unfavorable acquired lease contracts are being amortized over the contract term, including anticipated renewals and terminations.

The following presents a summary of favorable and unfavorable lease contracts:



	Favorable						Unfavorable
	December 31,						December 31,
(millions)	2017			2016			2017			2016
Acquired fair value of lease contracts	$	65.2		$	73.0		$	(81.3	)	$	(82.6	)
Accumulated (amortization) accretion	(41.9		)	(43.0		)	49.8			42.4
Total acquired fair value of lease contracts, net	$	23.3		$	30.0		$	(31.5	)	$	(40.2	)

The table below shows the amortization expense for favorable acquired lease contracts, which is recognized as an increase to Cost of parking services - Lease contracts within the Consolidated Statements of Income for the years ended December 31, 2017, 2016 and 2015, along with the weighted average remaining useful life.



	Year Ended December 31,
(millions)	2017		2016		2015
Amortization expense	$	6.6	$	8.3	$	10.1
Weighted average life (years)	14.1		11.9		11.1

The table below shows the amortization expense for unfavorable acquired lease contracts, which is recognized as a decrease to Cost of parking services - Lease contracts within the Consolidated Statements of Income, for the years ended December 31, 2017, 2016 and 2015, along with the weighted average remaining useful life.



	Year Ended December 31,
(millions)	2017		2016		2015
Amortization expense	$	8.8	$	10.1	$	11.0
Weighted average life (years)	10.7		10.5		10.1

The expected future amortization (accretion) of acquired lease contracts is as follows:



(millions)	Favorable		Unfavorable			Unfavorable, Net
2018	$	4.0	$	(6.7	)	$	(2.7	)
2019	3.6		(5.6		)	(2.0		)
2020	3.0		(3.7		)	(0.7		)
2021	2.3		(2.8		)	(0.5		)
2022	1.6		(2.6		)	(1.0		)
2023 and Thereafter	8.8		(10.1		)	(1.3		)
Total	$	23.3	$	(31.5	)	$	(8.2	)