Inventories

We value our raw materials, work in process, and finished goods inventories using lower of cost, as determined by the average cost method, or market. Supplies and materials are valued at the first-in, first-out (FIFO) or average cost methods.

The components of inventories were as follows (dollars in millions):



	September 30, 2015		December 31, 2014
Raw materials	$	271.5	$	261.9
Work in process	13.9		11.3
Finished goods	206.3		216.3
Supplies and materials	204.2		175.4
Inventories	$	695.9	$	664.9