Inventories

9 Months Ended

Sep. 30, 2019

Inventory Disclosure [Abstract]

Inventories

Inventories

($ in millions)	September 30, 2019		December 31, 2018
Finished products		$1,159		$1,105
Work in process	207		193
Raw materials	460		452
Supplies	34		33
Total Inventories		$1,860		$1,783

Most U.S. inventories are valued using the last-in, first-out method. These inventories represented approximately 34% and 36% of total inventories at September 30, 2019 and December 31, 2018, respectively. If the first-in, first-out method of inventory valuation had been used, inventories would have been $127 million and $113 million higher as of September 30, 2019 and December 31, 2018, respectively.