LONG-TERM DEBT

We provide detail on our long-term debt balances in the following table as of the end of the 2015 second quarter and year-end 2014:



	At Period End
($ in millions)	June 30, 2015			December 31, 2014
Senior Notes:
Series G, interest rate of 5.8%, face amount of $316, maturing November 10, 2015 (effective interest rate of 6.8%)	$	315		$	314
Series H, interest rate of 6.2%, face amount of $289, maturing June 15, 2016 (effective interest rate of 6.3%)	289			289
Series I, interest rate of 6.4%, face amount of $293, maturing June 15, 2017 (effective interest rate of 6.5%)	293			293
Series K, interest rate of 3.0%, face amount of $600, maturing March 1, 2019 (effective interest rate of 4.4%)	597			596
Series L, interest rate of 3.3%, face amount of $350, maturing September 15, 2022 (effective interest rate of 3.4%)	349			349
Series M, interest rate of 3.4%, face amount of $350, maturing October 15, 2020 (effective interest rate of 3.6%)	348			348
Series N, interest rate of 3.1%, face amount of $400, maturing October 15, 2021 (effective interest rate of 3.4%)	398			397
Commercial paper, average interest rate of 0.5% at June 30, 2015	1,211			1,072
$2,000 Credit Facility	—			—
Other	117			123
	3,917			3,781
Less current portion classified in:
Current portion of long-term debt	(614		)	(324		)
	$	3,303		$	3,457

All of our long-term debt is recourse to us but unsecured. We paid cash for interest, net of amounts capitalized, of $54 million in the 2015 first half and $41 million in the 2014 first half.

We are a party to a multicurrency revolving credit agreement (the “Credit Facility”) that provides for $2,000 million of aggregate borrowings to support general corporate needs, including working capital, capital expenditures, share repurchases, and letters of credit. The availability of the Credit Facility also supports our commercial paper program. Borrowings under the Credit Facility generally bear interest at LIBOR (the London Interbank Offered Rate) plus a spread, based on our public debt rating. We also pay quarterly fees on the Credit Facility at a rate based on our public debt rating. While any outstanding commercial paper borrowings and/or borrowings under our Credit Facility generally have short-term maturities, we classify the outstanding borrowings as long-term based on our ability and intent to refinance the outstanding borrowings on a long-term basis. The Credit Facility expires on July 18, 2018. See the “Cash Requirements and Our Credit Facilities” caption later in this report in the “Liquidity and Capital Resources” section for information on our available borrowing capacity at June 30, 2015.

The following table presents future principal payments that are due for our debt as of the end of the 2015 second quarter:



Debt Principal Payments ($ in millions)	Amount
2015	$	321
2016	298
2017	301
2018	1,220
2019	607
Thereafter	1,170
Balance at June 30, 2015	$	3,917