
3.	INVENTORIES

Inventories consisted of the following (in millions):



	June 30, 2017		December 31, 2016
Refinery feedstocks	$	2,254	$	2,068
Refined petroleum products and blendstocks	2,941		3,153
Ethanol feedstocks and products	227		238
Materials and supplies	252		250
Inventories	$	5,674	$	5,709

Inventories are valued at the lower of cost or market. As of December 31, 2015, we had a valuation reserve of $766 million in order to state our inventories at market. We recorded a change in our lower of cost or market inventory valuation reserve that resulted in a net benefit to our results of operations of $454 million and $747 million for the three and six months ended June 30, 2016, respectively.

As of June 30, 2017 and December 31, 2016, the replacement cost (market value) of LIFO inventories exceeded their LIFO carrying amounts by $1.1 billion and $1.9 billion, respectively. As of June 30, 2017 and December 31, 2016, our non-LIFO inventories accounted for $421 million and $641 million, respectively, of our total inventories.