Notes to Consolidated Financial Statements

For the years ended December 31, 2014 and 2013

15. Long-term debt

  2015 2014
Unsecured debentures    
Series D – 5.67% debentures due September 2, 2019 $497,954 $497,465
Series E – 3.75% debentures due November 14, 2022 398,097 397,857
Series F – 5.09% debentures due November 14, 2042 99,243 99,230
Series G – 4.19% debentures due June 24, 2024 496,943 496,646
Total $1,492,237 $1,491,198

On June 24, 2014, Cameco issued $500,000,000 of Series G debentures and announced the early redemption of the outstanding Series C debentures. The Series G debentures bear interest at a rate of 4.19% per annum. The net proceeds of the issue after deducting expenses were approximately $496,400,000. The debentures mature on June 24, 2024 and are being amortized at an effective interest rate of 4.28%. The $300,000,000 principal amount of the Series C debentures was redeemed on July 16, 2014. The company incurred total charges of $12,135,000 in relation to the early redemption of these debentures (note 20).

Cameco has a $1,250,000,000 unsecured revolving credit facility that is available until November 1, 2019. Upon mutual agreement, the facility can be extended for an additional year on the anniversary date. In addition to direct borrowings under the facility, up to $100,000,000 can be used for the issuance of letters of credit and, to the extent necessary, it may be used to provide liquidity support for the Company’s commercial paper program. The agreement also provides the ability to increase the revolving credit facility above $1,250,000,000 by increments no less than $50,000,000, to a total of $1,750,000,000. The facility ranks equally with all of Cameco’s other senior debt. As of December 31, 2015 and 2014, there were no amounts outstanding under this facility.

Cameco has $1,490,809,000 (2014 – $1,068,420,000) in letter of credit facilities. Outstanding and committed letters of credit at December 31, 2015 amounted to $1,384,061,000 (2014 – $950,716,000), the majority of which relate to future decommissioning and reclamation liabilities (note 17).

Cameco is bound by a covenant in its revolving credit facility. The covenant requires a funded debt to tangible net worth ratio equal to or less than 1:1. Non–compliance with this covenant could result in accelerated payment and termination of the revolving credit facility. At December 31, 2015, Cameco was in compliance with the covenant and does not expect its operating and investing activities in 2016 to be constrained by it.

The table below represents currently scheduled maturities of long-term debt:

2016 2017 2018 2019 2020 Thereafter Total
$ — 497,954 994,283 $1,492,237