effective tax rate for 2015 was 36.8% . We expect our annual effective tax rate to be between 35% and 36% for 2016. The expected reduction in our rate from prior years is primarily related to differences in our global tax rates. In certain periods we may have adjustments to our deferred tax assets as a result of changes in prior year estimates and tax laws enacted during the period, which will impact the effective tax rate for that period. At December 31, 2015 , we had approximately $9.5 billion of U.S. federal pre-tax net operating loss carryforwards, which do not begin to expire until 2024 . Accordingly, we believe we will not pay any cash federal income taxes before 2018. See Note 11 of the Notes to the Consolidated Financial Statements for more information.

We released substantially all of our valuation allowance against our net deferred tax assets on December 31, 2013. The release of the allowance primarily resulted in a net tax benefit of $8.0 billion that was recorded in income tax (provision) benefit in our Consolidated Statement of Operations.

Refinery Segment

The refinery primarily produces gasoline, diesel and jet fuel. Monroe exchanges substantially all the non-jet fuel products the refinery produces with third parties for jet fuel consumed in our airline operations. The jet fuel produced and procured through exchanging gasoline and diesel fuel produced by the refinery provided approximately 171,000 barrels (approximately seven million gallons) per day for use in our airline operations during 2015 . We believe that the increase in jet fuel supply due to the refinery's operation has reduced the overall market price of jet fuel, and thus lowered our cost of jet fuel.

A refinery is subject to annual EPA requirements to blend renewable fuels into the gasoline and on-road diesel fuel it produces. Alternatively, a refinery may purchase renewable energy credits, called RINs, from third parties in the secondary market. Because the refinery operated by Monroe does not blend renewable fuels, it must purchase its entire RINs requirement in the secondary market or obtain a waiver from the EPA. We recognized $75 million, $111 million and $64 million of expense related to the RINs requirement in 2015, 2014 and 2013, respectively. We are in possession of the RINs needed to satisfy our 2013 obligation and a portion of our 2014 and 2015 obligations.

The refinery recorded a profit of $290 million in 2015 , compared to $96 million in 2014 and a loss of $116 million recorded in 2013. The refinery's profitability improved year-over-year despite lower revenues resulting from a decline in refined fuel market prices. The refinery’s increase in profits was attributable to higher product crack spreads and higher throughput as a result of enhanced operational reliability, logistical improvements and utilization of intermediates (partially refined fuels). For more information regarding the refinery’s results, see Note 14 of the Notes to the Consolidated Financial Statements.

Financial Condition and Liquidity

We expect to meet our cash needs for the next 12 months from cash flows from operations, cash and cash equivalents, short-term investments and