LONG-TERM DEBT

We provide detail on our long-term debt balances, net of discounts, premiums, and debt issuance costs, in the following table at year-end 2018 and 2017:



($ in millions)	At Year-End 2018			At Year-End 2017
Senior Notes:
Series K Notes, interest rate of 3.0%, face amount of $600, maturing March 1, 2019 (effective interest rate of 4.4%)	$	600		$	598
Series L Notes, interest rate of 3.3%, face amount of $350, maturing September 15, 2022 (effective interest rate of 3.4%)	349			348
Series M Notes, interest rate of 3.4%, face amount of $350, maturing October 15, 2020 (effective interest rate of 3.6%)	349			348
Series N Notes, interest rate of 3.1%, face amount of $400, maturing October 15, 2021 (effective interest rate of 3.4%)	397			397
Series O Notes, interest rate of 2.9%, face amount of $450, maturing March 1, 2021 (effective interest rate of 3.1%)	448			447
Series P Notes, interest rate of 3.8%, face amount of $350, maturing October 1, 2025 (effective interest rate of 4.0%)	345			345
Series Q Notes, interest rate of 2.3%, face amount of $750, maturing January 15, 2022 (effective interest rate of 2.5%)	745			744
Series R Notes, interest rate of 3.1%, face amount of $750, maturing June 15, 2026 (effective interest rate of 3.3%)	743			743
Series S Notes, interest rate of 6.8%, face amount of $324, matured May 15, 2018 (effective interest rate of 1.7%)	—			330
Series T Notes, interest rate of 7.2%, face amount of $181, maturing December 1, 2019 (effective interest rate of 2.3%)	188			197
Series U Notes, interest rate of 3.1%, face amount of $291, maturing February 15, 2023 (effective interest rate of 3.1%)	291			291
Series V Notes, interest rate of 3.8%, face amount of $318, maturing March 15, 2025 (effective interest rate of 2.8%)	335			337
Series W Notes, interest rate of 4.5%, face amount of $278, maturing October 1, 2034 (effective interest rate of 4.1%)	292			292
Series X Notes, interest rate of 4.0%, face amount of $450, maturing April 15, 2028 (effective interest rate of 4.2%)	443			—
Series Y Notes, floating rate, face amount of $550, maturing December 1, 2020 (effective interest rate of 3.2% at December 31, 2018)	547			—
Series Z Notes, interest rate of 4.2%, face amount of $350, maturing December 1, 2023 (effective interest rate of 4.4%)	347			—
Series AA Notes, interest rate of 4.7%, face amount of $300, maturing December 1, 2028 (effective interest rate of 4.8%)	297			—

Commercial paper	2,245			2,371
Credit Facility	—			—
Capital lease obligations	163			171
Other	223			279
	$	9,347		$	8,238
Less: Current portion of long-term debt	(833		)	(398		)
	$	8,514		$	7,840

All our long-term debt is recourse to us but unsecured. All the Senior Notes shown in the table above are our unsecured and unsubordinated obligations, which rank equally with our other Senior Notes and all other unsecured and unsubordinated indebtedness that we have issued or will issue from time to time, and are governed by the terms of an indenture, dated as of November 16, 1998, between us and The Bank of New York Mellon (formerly The Bank of New York), as trustee. With the exception of the floating rate Series Y Notes, we may redeem some or all of each series of the Senior Notes before maturity under the terms provided in the applicable form of Senior Note.

We are party to a multicurrency revolving credit agreement (the “Credit Facility”) that provides for up to $4 billion of aggregate effective borrowings to support our commercial paper program and general corporate needs, including working capital, capital expenditures, share repurchases, letters of credit, and acquisitions. 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 June 10, 2021. See the “Cash Requirements and Our Credit Facility” caption earlier in this report in the “Liquidity and Capital Resources” section of Item 7 above for further information on our Credit Facility and available borrowing capacity at December 31, 2018.

In the 2018 fourth quarter, we issued $550 million aggregate principal amount of three-month LIBOR plus 0.600 percent Series Y Notes due December 1, 2020 (the “Series Y Notes”), $350 million aggregate principal amount of 4.150 percent Series Z Notes due December 1, 2023 (the “Series Z Notes”), and $300 million aggregate principal amount of 4.650 percent Series AA Notes due December 1, 2028 (the “Series AA Notes”). We will pay interest on the Series Y Notes on March 1, June 1, September 1, and December 1 of each year, commencing on March 1, 2019, and will pay interest on the Series Z Notes and the Series AA Notes on June 1 and December 1 of each year, commencing on June 1, 2019. We received net proceeds of approximately $1,190 million from the offering of the Series Y Notes, the Series Z Notes, and the Series AA Notes, after deducting the underwriting discount and estimated expenses.

In the 2018 second quarter, we issued $450 million aggregate principal amount of 4.000 percent Series X Notes due April 15, 2028 (the “Series X Notes”). We will pay interest on the Series X Notes on April 15 and October 15 of each year, commencing on October 15, 2018. We received net proceeds of approximately $443 million from the offering of the Series X Notes, after deducting the underwriting discount and estimated expenses.

The proceeds from our 2018 senior note issuances were made available for general corporate purposes, which may include working capital, capital expenditures, acquisitions, stock repurchases, or repayment of outstanding commercial paper or other borrowings.

The following table presents future principal payments, net of discounts, premiums, and debt issuance costs, for our debt as of year-end 2018:



Debt Principal Payments ($ in millions)	Amount
2019	$	833
2020	912
2021	3,108
2022	1,114
2023	695
Thereafter	2,685
Balance at year-end 2018	$	9,347

We paid cash for interest, net of amounts capitalized, of $290 million in 2018, $234 million in 2017, and $165 million in 2016.