Inventories

Inventories are valued at the lower of first-in, first-out cost or market. Cost includes applicable material, labor and overhead. Inventories consisted of the following:



	March 31, 2018		December 31, 2017
Raw materials	$	68,842	$	73,026
Work in process	10,723		10,136
Finished goods	15,072		15,853
	$	94,637	$	99,015

Inventories on-hand are regularly reviewed and, when necessary, provisions for excess and obsolete inventory are recorded based primarily on our estimated production requirements, which reflect expected market volumes. Excess and obsolete provisions may vary by product depending upon future potential use of the product.