Other income (expense), net was $10.4 million in 2017, $8.3 million in 2016 and $46.7 million in 2015. In 2017, the expense was primarily due to foreign currency exchange losses. In 2016, the expense was primarily related to $16.1 million of unrealized and realized losses on fuel swap derivative hedge contracts partially offset by $4.5 million of gains on foreign currency exchange and $3.9 million of gains on foreign currency exchange derivative hedge contracts. In 2015, the expense was primarily related to $30.7 million of losses from the dedesignation of certain fuel swap derivative hedge contracts and the ineffectiveness of settled fuel swaps in 2015. Also included in 2015 was an expense of $26.2 million related to the fair value adjustment of a foreign exchange collar which did not receive hedge accounting treatment partially offset by $11.0 million of foreign currency transaction gains.