Inventory

Inventories are stated at the lower of cost and net realizable value. Cost is determined using the weighted average cost of raw materials, which approximates the first-in, first-out (“FIFO”) method and includes allocations of manufacturing labor and overhead. Included in finished goods at March 31, 2019 and December 31, 2018 was $1.3 million and $1.4 million, respectively, of trial and evaluation hardware units. Provisions are made to reduce excess, obsolete or slow-moving inventories to their net realizable value. Inventory consisted of the following at March 31, 2019 and December 31, 2018 (in thousands):



	March 31, 2019		December 31, 2018
Raw materials	$	20,574	$	19,670
Finished goods	17,013		14,093
Total inventory	$	37,587	$	33,763