United states securities and exchange commission

(1) Amended to reflect the adoption of new guidance related to the presentation of debt issuance costs as described in Note 2 “Summary of Significant Accounting Principles and Practices.”

On May 27, 2016, $500 million of 3.125% Senior Notes due May 2016 issued by Aon Corporation matured and were repaid in full.

On March 1, 2016, Aon plc issued $750 million of 3.875% Senior Notes due December 2025. The Company used the proceeds of the issuance for general corporate purposes.

On November 13, 2015, Aon plc issued $400 million of 2.80% Senior Notes due March 2021. The Company used the proceeds of the issuance for general corporate purposes.

On September 30, 2015, $600 million of 3.50% Senior Notes issued by Aon Corporation matured and were repaid in full.

On May 20, 2015, Aon plc issued $600 million of 4.750% Senior Notes due May 2045. The Company used the proceeds of the issuance for general corporate purposes.

Each of the notes issued by Aon plc and described above is fully and unconditionally guaranteed by Aon Corporation. The 4.76% Senior Notes due March 2018 identified in the table above were issued by a Canadian subsidiary of Aon Corporation and are fully and unconditionally guaranteed by Aon plc and Aon Corporation. Refer to Note 16 “Guarantee of Registered Securities” for additional information regarding guarantees of outstanding debt securities. Each of the notes described above and identified in the table above contains customary representations, warranties and covenants, and the Company was in compliance with all such covenants as of December 31, 2016 .
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Repayments of total debt are as follows (in millions):

2017	$	336
2018	278
2019	—
2020	600
2021	400
Thereafter	4,700
Total Repayments	6,314
Unamortized discount, premium, and debt issuance cost	(109		)
Total Debt	$	6,205

Revolving Credit Facilities

As of December 31, 2016 , Aon plc had two primary committed credit facilities outstanding: its $400 million U.S. credit facility expiring in March 2017 (the “2017 Facility”) and its $900 million multi-currency U.S. credit facility expiring in February 2021 (the “2021 Facility”). The Company plans to let the 2017 facility expire but may evaluate obtaining additional committed credit in the future. Each of these facilities includes customary representations, warranties and covenants, including financial covenants that require Aon plc to maintain specified ratios of adjusted consolidated EBITDA to consolidated interest expense and consolidated debt to adjusted consolidated EBITDA, in each case, tested quarterly. At December 31, 2016 , Aon plc did not have borrowings under either the 2017 Facility or the 2021 Facility, and was in compliance with all covenants contained therein during the twelve months ended December 31, 2016 .

Commercial Paper

Aon Corporation, a wholly-owned subsidiary of Aon plc, has established a U.S. commercial paper program, which provides for commercial paper to be issued in an aggregate principal amount of up to $900 million , and Aon plc has established a European multi-currency commercial paper program that provides for commercial paper to be issued in an aggregate principal amount of up to €300 million . The U.S. commercial paper program is fully and unconditionally guaranteed by Aon plc and the European commercial paper program is fully and unconditionally guaranteed by Aon Corporation. In the aggregate, the Company had $329.2 million and $50.0 million of commercial paper outstanding at December 31, 2016 and 2015 , respectively, which was included in Short-term debt and current portion of long-term debt in the Company’s Consolidated Statements of Financial Position. The weighted average commercial paper outstanding for 2016 and 2015 was $265.0 million and $402.0 million , respectively. The weighted average interest rate of the commercial paper outstanding during 2016 and 2015 was 0.22% and 0.50% , respectively.

7.     Lease Commitments

The Company leases office facilities, equipment, and automobiles under non-cancelable operating leases. These leases expire at various dates and may contain renewal and expansion options. In addition to base rental costs, occupancy lease agreements generally provide for rent escalations resulting from increased assessments for real estate taxes and other charges. The Company’s lease obligations are primarily for the use of office space.

Rental expenses (including amounts applicable to taxes, insurance and maintenance) for operating leases are as follows (in millions):

Years ended December 31	2016				2015				2014
Rental expense	$	400			$	454			$	455
Less: Sub lease rental income	(64		)		(83		)		(75		)
Net rental expense	$	336			$	371			$	380

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At December 31, 2016 , future minimum rental payments required under operating leases that have initial or remaining non-cancelable lease terms in excess of one year are as follows (in millions):

Years ended December 31, 2016	Gross rental commitments				Rentals from subleases				Net rental commitments
2017	$	355			$	(55	)		$	300
2018	317				(44		)		273
2019	283				(38		)		245
2020	237				(34		)		203
2021	214				(33		)		181
Thereafter	696				(47		)		649
Total minimum payments required	$	2,102			$	(251	)		$	1,851