Leases

We lease substantially all our office space under operating leases and certain equipment under operating and capital leases that expire at various dates. Office leases may provide for additional renewal periods at our option. In circumstances where the exercise of the renewal option is reasonably assured at the inception of the lease, the renewal period is included in the determination of the lease term. Office leases may include scheduled rent increases and concessions, such as rent abatements and landlord incentives and tenant improvement allowances. Scheduled rent increases are recognized on a straight-line basis over the lease term. Concessions are recorded as deferred rent and are amortized to rent expense on a straight-line basis over the lease term. Certain office leases require payment of real estate taxes and other occupancy costs. These costs are not included in rent expense. Leasehold improvements made at inception or during the lease term are amortized over the shorter of the asset life or the lease term, which may include renewal periods where the renewal is reasonably assured.

Rent expense for the three years ended December 31, 2012, was (in millions):



	2012		2011		2010
Office base rent	$	390.5	$	381.6	$	374.4
Less third party sublease rent	10.4		12.8		16.3


Net office rent	380.1		368.8		358.1
Equipment rent	36.3		42.7		46.4


	$	416.4	$	411.5	$	404.5

Future minimum lease payments under non-cancelable operating and capital leases, reduced by third party sublease rent receivable from existing non-cancelable subleases, are (in millions):



	Operating Leases						Capital Leases
	Gross Rent		Less Sublease Rent		Net Rent		Minimum Lease Payments
2013	$	399.7	$	7.6	$	392.1	$	24.1
2014	298.7		6.0		292.7		15.6
2015	229.3		4.0		225.3		8.5
2016	170.0		1.3		168.7		4.5
2017	146.5		1.0		145.5		3.2
Thereafter	359.4		0.2		359.2		3.1


	$	1,603.6	$	20.1	$	1,583.5


Total minimum lease payments							59.0
Less interest component							1.7


Present value of minimum lease payments							$	57.3

Property under capital lease and capital lease obligations as of December 31, 2012 and 2011 were (in millions):



	2012			2011
Property under capital lease:
Cost	$	126.3		$	111.4
Accumulated depreciation	(71.3		)	(59.4		)

	$	55.0		$	52.0


Capital lease obligations:
Current	$	23.4		$	24.1
Long-term	33.9			31.8

	$	57.3		$	55.9

Depreciation expense for property under capital lease was $25.9 million, $25.0 million and $23.0 million in 2012, 2011 and 2010, respectively.