9. Long-term Debt

A summary of Long-term Debt follows:

(Stated in millions)

	Mar. 31,		Dec. 31,
	2017		2016
4.00% Senior Notes due 2025	$	1,740	$	1,740
3.30% Senior Notes due 2021		1,594		1,594
3.00% Senior Notes due 2020		1,591		1,591
3.65% Senior Notes due 2023		1,491		1,491
2.35% Senior Notes due 2018		1,297		1,297
4.20% Senior Notes due 2021		1,100		1,100
2.40% Senior Notes due 2022		996		996
3.63% Senior Notes due 2022		845		845
0.63% Guaranteed Notes due 2019		645		622
1.50% Guaranteed Notes due 2019		551		536
6.38% Notes due 2018		294		297
7.00% Notes due 2038		214		214
4.50% Notes due 2021		137		137
5.95% Notes due 2041		116		116
3.60% Notes due 2022		110		110
5.13% Notes due 2043		99		99
4.00% Notes due 2023		82		83
3.70% Notes due 2024		56		56
Commercial paper borrowings		2,503		2,421
Other		1,077		1,118
	$	16,538	$	16,463

The estimated fair value of Schlumberger’s Long-term Debt, based on quoted market prices, was $16.8 billion at both March 31, 2017 and December 31, 2016.

Borrowings under the commercial paper program at March 31, 2017 were $2.9 billion, of which $2.5 billion was classified within Long-term Debt and $0.4 billion was classified within Short-term borrowings and current portion of long-term debt in the Consolidated Balance Sheet. At December 31, 2016, borrowings under the commercial paper program were $2.6 billion, of which $2.4 billion was classified within Long-term debt and $0.2 billion was classified in Short-term borrowings and current portion of long-term debt in the Consolidated Balance Sheet.