PROPERTY:

12 Months Ended

Dec. 31, 2017

PROPERTY:

PROPERTY:

NOTE 5—PROPERTY:

	At December 31,
(in millions)	2017			2016
Buildings and equipment	$	12,552.8		$	12,177.1
Construction in progress		2,301.9			1,811.8
Mine development		267.9			259.1
Mineral assets		83.2			83.2
Land, other than mineral		218.4			142.1
Total property		15,424.2			14,473.3
Accumulated depreciation, amortization and depletion		(6,324.6	)		(5,706.8	)
Total property and mine development, net	$	9,099.6		$	8,766.5

        Construction in progress increased in 2017 as a result of the spending on the Company expansion projects. For more detailed information, please see Item 7 "Management Discussion and Analysis of Financial Condition and Results of Operations—Capital Investment Program."

        Depreciation and depletion expense for the years ended December 31, 2017, 2016 and 2015, amounted to $665.2 million, $639.1 million and $503.6 million, respectively.