Inventories

Inventories (principally using the LIFO method) are comprised of the following:



	December 31,
(Millions of dollars)	2017		2016
Raw materials	$	2,802	$	2,102
Work-in-process	2,254		1,719
Finished goods	4,761		4,576
Supplies	201		217
Total inventories	$	10,018	$	8,614

During 2017, inventory quantities were reduced. This reduction resulted in a liquidation of LIFO inventory resulting mostly from closure of our facility in Gosselies, Belgium. The liquidated inventory was carried at lower costs prevailing in prior years as compared with current costs. In 2017, the effect of this reduction in inventory decreased Cost of goods sold by approximately $66 million and increased Profit by approximately $49 million or $0.08 per share.

We had long-term material purchase obligations of approximately $813 million at December 31, 2017.