11. Debt

Debt was as follows:

	Fiscal Year End
	2016			2015
	(in millions)
Commercial paper, at a weighted-average interest rate of 0.69% at fiscal year end 2016	$	330		$	—
Senior floating rate notes due 2016(1)		—			500
6.55% senior notes due 2017		708			708
2.375% senior notes due 2018		325			325
2.35% senior notes due 2019		250			250
4.875% senior notes due 2021		250			250
3.50% senior notes due 2022		500			500
1.100% euro-denominated senior notes due 2023		618			614
3.45% senior notes due 2024		250			250
3.700% senior notes due 2026		350			—
7.125% senior notes due 2037		477			477
Other		3			—

Total principal debt		4,061			3,874
Unamortized discounts and debt issuance costs		(26	)		(27	)
Effects of fair value hedge-designated interest rate swaps		35			37

Total debt	$	4,070		$	3,884


(1)	The senior floating rate notes due 2016 bore interest at a rate of three-month London interbank offered rate ("LIBOR") plus 0.20% per year.

During January 2016, Tyco Electronics Group S.A. ("TEGSA"), our 100%-owned subsidiary, issued $350 million aggregate principal amount of 3.700% senior notes due February 15, 2026. The notes are TEGSA's unsecured senior obligations and rank equally in right of payment with all existing and any future senior indebtedness of TEGSA and senior to any subordinated indebtedness that TEGSA may incur.

TEGSA has a five-year unsecured senior revolving credit facility ("Credit Facility") with total commitments of $1,500 million. The Credit Facility was amended in December 2015 primarily to extend the maturity date from August 2018 to December 2020. TEGSA had no borrowings under the Credit Facility at fiscal year end 2016 and 2015.

Borrowings under the Credit Facility bear interest at a rate per annum equal to, at the option of TEGSA, (1) LIBOR plus an applicable margin based upon the senior, unsecured, long-term debt rating of TEGSA, or (2) an alternate base rate equal to the highest of (i) Bank of America, N.A.'s base rate, (ii) the federal funds effective rate plus 1/2 of 1%, and (iii) one-month LIBOR plus 1%, plus, in each case, an applicable margin based upon the senior, unsecured, long-term debt rating of TEGSA. TEGSA is required to pay an annual facility fee ranging from 5.0 to 12.5 basis points based upon the amount of the lenders' commitments under the Credit Facility and the applicable credit ratings of TEGSA.

The Credit Facility contains a financial ratio covenant providing that if, as of the last day of each fiscal quarter, our ratio of Consolidated Total Debt to Consolidated EBITDA (as defined in the Credit Facility) for the then most recently concluded period of four consecutive fiscal quarters exceeds 3.75 to 1.0, an Event of Default (as defined in the Credit Facility) is triggered. The Credit Facility and our other debt agreements contain other customary covenants.

Periodically, TEGSA issues commercial paper to U.S. institutional accredited investors and qualified institutional buyers in accordance with available exemptions from the registration requirements of the Securities Act of 1933 as part of our ongoing effort to maintain financial flexibility and to potentially decrease the cost of borrowings. Borrowings under the commercial paper program are backed by the Credit Facility.

TEGSA's payment obligations under its senior notes, commercial paper, and Credit Facility are fully and unconditionally guaranteed by its parent, TE Connectivity Ltd.

Principal payments required for debt are as follows:

	(in millions)
Fiscal 2017	$	331
Fiscal 2018		708
Fiscal 2019		576
Fiscal 2020		1
Fiscal 2021		250
Thereafter		2,195

Total	$	4,061

The fair value of our debt, based on indicative valuations, was approximately $4,424 million and $4,115 million at fiscal year end 2016 and 2015, respectively.