SHORT-TERM DEBT

Short-term debt consisted of the following (in thousands of dollars):



	As of December 31,
	2016			2015
Lines of Credit
Outstanding at December 31	$	16,392		$	23,072
Maximum month-end balance during the year	$	24,722		$	47,802
Weighted average interest rate during the year	4.04		%	4.37		%
Weighted average interest rate at December 31	5.13		%	3.16		%

Commercial Paper
Outstanding at December 31	$	369,748		$	330,000
Maximum month-end balance during the year	$	629,712		$	330,000
Weighted average interest rate during the year	0.50		%	0.23		%
Weighted average interest rate at December 31	0.69		%	0.47		%

Lines of Credit

The Company's U.S. business had a committed line of credit of $900 million in 2016 and 2015 for which the Company paid a commitment fee of 0.07% in 2016 and 2015. This line of credit supports the issuance of commercial paper. The current line is due to expire in August 2018.

Foreign subsidiaries also utilize lines of credit to meet business growth and operating needs. The Company had $88 million and $100 million of uncommitted lines of credit at December 31, 2016 and 2015, respectively.

Commercial Paper

The Company issued commercial paper for general working capital needs.

Letters of Credit

The Company's U.S. business had $30 million and $29 million of letters of credit at December 31, 2016 and 2015, respectively, primarily related to the Company's insurance program. Letters of credit were also issued to facilitate purchases of products. These issued amounts were $5 million and $3 million at December 31, 2016 and 2015, respectively. Letters of credit issued by the Company's international businesses were immaterial.