earnings were $18.5 billion in 2012 compared with $18.3 billion in 2011. The increase was mainly due to the gain of approximately $1.4 billion on an asset exchange in Australia, higher natural gas realizations of about $610 million and the nearly $600 million gain on sale of an equity interest in the Wheatstone Project. Mostly offsetting these effects were lower crude oil volumes of about $1.3 billion and higher exploration expenses of about $430 million. Foreign currency effects decreased earnings by $275 million in 2012, compared with an increase of $211 million a year earlier.

The company’s average realization for international crude oil and natural gas liquids in 2013 was $100.26 per barrel, compared with $101.88 in 2012 and $101.53 in 2011. The average natural gas realization was $5.91 per thousand cubic feet in 2013, compared with $5.99 and $5.39 in 2012 and 2011, respectively.

International net oil-equivalent production of 1.94 million barrels per day in 2013 decreased 1 percent from 2012 and decreased about 3 percent from 2011. Project ramp-ups in Nigeria and Angola in 2013 were more than offset by normal field declines. The decline between 2012 and 2011 was a result of new production in Thailand and Nigeria in 2012 being more than offset by normal field declines, the shut-in of the Frade Field in Brazil and a major planned turnaround at Tengizchevroil.

The net liquids component of international oil-equivalent production was 1.3 million barrels per day in 2013, a decrease of approximately 2 percent from 2012 and a decrease of approximately 7 percent from 2011. International net natural gas production of 3.9 billion cubic feet per day in 2013 was up 2 percent from 2012 and up 8 percent from 2011.

Refer to the “Selected Operating Data” table, on page FS-10, for a three-year comparative of international production volumes.

U.S. Downstream

U.S. downstream operations earned $787 million in 2013, compared with $2.0 billion in 2012. The decrease was mainly due to lower margins on refined product sales of $860 million and higher operating expenses of $600 million reflecting repair and maintenance activities at the company's refineries. The decrease was partially offset by higher earnings of $150 million from the 50 percent-owned CPChem.

U.S. downstream operations earned $2.0 billion in 2012, compared with $1.5 billion in 2011. The increase was mainly due to higher margins on refined products sales of $520 and higher earnings of $140 from CPChem. These benefits were partly offset by higher operating expenses of $130 million.

Refined product sales of 1.18 million barrels per day in 2013 declined 2 percent, mainly reflecting lower gas oil, kerosene and gasoline sales. Sales volumes of refined products were 1.21 million barrels per day in 2012, a decrease of 4 percent from 2011, mainly reflecting lower gasoline and fuel oil sales. U.S. branded gasoline sales of 517,000 barrels per day in 2013 were essentially unchanged from 2012 and 2011.

Refer to the “Selected Operating Data” table on page FS-10 for a three-year comparison of sales volumes of gasoline and other refined products and refinery input volumes.

International