Revenue Earning Equipment

Revenue earning equipment consists of the following (in millions):



	December 31, 2017			December 31, 2016
Revenue earning equipment	$	3,757.2		$	3,695.5
Less: Accumulated depreciation	(1,382.6		)	(1,305.5		)
Revenue earning equipment, net	$	2,374.6		$	2,390.0

Depreciation rates on the Company's revenue earning equipment are reviewed regularly based on management's ongoing assessment of present and estimated future market conditions, their effect on residual values at the time of disposal and estimated holding periods. The impact of depreciation rate changes increased expense $18.0 million, $9.4 million and $1.9 million for the years ended December 31, 2017, 2016 and 2015, respectively.

For certain equipment at or nearing the end of its useful life, the Company considers the option of refurbishing the equipment as an alternative to replacing it based upon the economics of each alternative. Therefore, the number of units refurbished each year can fluctuate based on several factors including the market conditions for used equipment sales and incentives offered by manufacturers of new equipment. The capitalized cost of refurbishing revenue earning equipment was $0.5 million, $6.5 million and $40.1 million for the years ended December 31, 2017, 2016 and 2015, respectively.

During 2017, the Company deemed certain revenue earning equipment, with a net book value of approximately $4.3 million, to be held for sale and reclassified such equipment to "Prepaid and other current assets" in the consolidated balance sheet. The Company also performed an impairment assessment of revenue earning equipment and recorded an impairment charge as discussed further in Note 6, "Impairment."