average realization for U.S. crude oil and natural gas liquids in 2017 was $44.53 per barrel, compared with $35.00 in 2016 and $42.70 in 2015. The average natural gas realization was $2.10 per thousand cubic feet in 2017, compared with $1.59 in 2016 and $1.92 in 2015.

Net oil-equivalent production in 2017 averaged 681,000 barrels per day, down 1 percent from 2016 and down 5 percent from 2015. Between 2017 and 2016, production increases from shale and tight properties in the Permian Basin in Texas and New Mexico and base business in the Gulf of Mexico were more than offset by the effect of asset sales of 59,000 barrels per day and normal field declines. Between 2016 and 2015, production increases from shale and tight properties in the Permian Basin in Texas and New Mexico, and base business were more than offset by the effect of asset sales and normal field declines.

The net liquids component of oil-equivalent production for 2017 averaged 519,000 barrels per day, up 3 percent from 2016 and 4 percent from 2015. Net natural gas production averaged about 970 million cubic feet per day in 2017, down 13 percent from 2016 and 26 percent from 2015, primarily as a result of asset sales. Refer to the “Selected Operating Data” table on page 39 for a three-year comparison of production volumes in the United States.

International Upstream

International upstream earnings were $4.51 billion in 2017, compared with a loss of $483 million in 2016. The increase in earnings was primarily due to higher crude oil realizations of $2.59 billion, higher natural gas sales volumes of $1.22 billion, higher gains on asset sales of $750 million, and lower operating expenses of $410 million. Foreign currency effects had an unfavorable impact on earnings of $578 million between periods.

International upstream incurred a loss of $483 million in 2016, compared with earnings of $2.09 billion in 2015. The decrease in earnings was primarily due to lower crude oil realizations of $1.89 billion, lower natural gas realizations of $600 million, lower gains on asset sales of $450 million and higher tax items of $330 million. Partially offsetting the decrease were lower exploration and operating expenses of $640 million and $520 million, respectively, and higher natural gas sales volumes of $330 million. Foreign currency effects had an unfavorable impact on earnings of $603 million between periods.

The company’s average realization for international crude oil and natural gas liquids in 2017 was $49.46 per barrel, compared with $38.61 in 2016 and $46.52 in 2015. The average natural gas realization was $4.62 per thousand cubic feet in 2017, compared with $4.02 and $4.53 in 2016 and 2015, respectively.

International net oil-equivalent production was 2.05 million barrels per day in 2017, up 8 percent from 2016 and 2015. Between 2017 and 2016, production increases from major capital projects and lower planned maintenance-related downtime were partially offset by production entitlement effects in several locations and normal field declines. Between 2016 and 2015, production increases from major capital projects, base business, and shale and tight properties were largely offset by