of 2012 to $9.9 billion at December 31, 2014 .  

 

In each of 2014 and 2012, we extinguished $1.6 billion of existing debt under our secured financing arrangements prior to scheduled maturity. In connection with the extinguishment, we recorded losses of $268 million and $118 million , respectively, for the difference between the principal paid and the carrying value of the debt, which included unamortized discounts or premiums and unamortized issuance costs. The unamortized debt discounts resulted from fair value adjustments recorded in the 2008 purchase accounting of Northwest Airlines. The losses also included premiums paid to retire the debt.  

 

Miscellaneous, net is unfavorable primarily due to our proportionate share of losses from our equity investment in Virgin Atlantic, foreign currency exchange rate losses and a charge associated with the devaluation of the Venezuelan bolivar. The loss from Virgin Atlantic primarily results from unfavorable MTM adjustments on fuel hedges.  

 

Income Taxes  

 

We consider all income sources, including other comprehensive income, in determining the amount of tax (provision) benefit allocated to continuing operations. The following table shows the components of our income tax (provision) benefit:   

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. Our annual effective tax rate for 2014 was 38.5% . At December 31, 2014 , we had over $12.0 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 during the next few years. See Note 13 of the Notes to the Consolidated Financial Statements for more information.  

 

During 2012, we did not record an income tax provision for U.S. federal income tax purposes since our deferred tax assets were fully reserved by a valuation allowance.  

 

Refinery Segment  

 

The refinery primarily produces gasoline, diesel and jet fuel. Under multi-year agreements, Monroe exchanges 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 150,000 barrels (approximately six million gallons) per day for use in airline operations during 2014 .  

 

A refinery is subject to EPA requirements that are established each year 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 $111 million and $64 million of expense related to the RINs requirement in 2014 and 2013, respectively, including