Afton Chemical recorded sales for the fourth quarter of 2015 of $476.7 million, down 13.0% versus the same period last year, due to lower shipments, foreign currency exchange and changes in selling prices and mix. Operating profit for the fourth quarter of 2015 was $75.3 million, an 11.9% decrease over fourth quarter operating profit last year of $85.5 million. The decrease was due to lower sales volume, changes in foreign currency exchange and increases in research and development investments, partially offset by lower raw material costs, according to the company.

For the year, petroleum additives sales were $2,125 million compared to sales in 2014 of $2,325 million, a decrease of 8.6%. This decrease was primarily due to foreign currency exchange, changes in selling prices and mix. Operating profit for petroleum additives for 2015 declined 2.6% to $374.9 million, compared to $385.1 million for 2014. Changes in foreign currency overshadowed strong operating performance in the Americas and, to a lesser extent, the Asia Pacific region. The decrease in operating profit was also due to increases in research and development investments and lower sales volume, partially offset by lower raw material costs.

Petroleum additives shipments for the fourth quarter of 2015 were down 4.3% from the same period last year. This decline, which represents the lowest level of quarterly shipments in three years, was primarily due to decreases in lubricant and fuel additives shipments in North America. For the year, shipments declined 1.2% versus 2014, with increases in fuel additives shipments, primarily in North America, offset by declines in lubricant additives in all regions except Latin America. The company said shipments were below its expectations for both the quarter and full year periods, as demand for lubricant products trended lower in the face of a continued general weakness in the global economy. In addition, the company said it believes the rapid decline in crude oil prices in the fourth quarter may have led some customers to reduce stock levels in anticipation of lower base oil prices.

Parent company NewMarket Corp. reported fourth-quarter earnings of $53.9 million compared to net income of $52.1 million, for the fourth quarter of 2014. Net income for 2015 was $238.6 million, compared to net income of $233.3 million for 2014. NewMarket said net income for all periods included the impact of valuing an interest rate swap at fair value. Excluding this item, fourth quarter 2015 earnings were $53.2 million compared to $53.7 million last year. On the same basis, earnings for the year 2015 were $240.6 million compared to $237.6 million last year.