Inventory consisted of the following at December 31, 2021 and 2020 (in thousands):


	2021		2020
Finished goods	$	515	$	600
Work-in-process		882		802
Raw materials and supplies		40,962		31,683
Inventory	$	42,359	$	33,085

We maintain certain surplus quantities of spare parts that serve as backup components and maintenance materials for our directional drilling and Colombia contract drilling operations. In 2021, advances in technologies rendered certain directional drilling equipment, and spare parts used to service that equipment, obsolete. Based on our assessment of limited alternative uses or active markets to recapture costs, we recorded a write-down of $4.0 million. The write-down is recorded in "Operating costs and expenses - Directional drilling" in the consolidated statements of operations.