Supplementary Information

12 Months Ended

Dec. 31, 2017

19. Supplementary Information

During 2015, Schlumberger entered into an agreement with one of its customers to receive certain fixed assets in lieu of payment of approximately $200 million of accounts receivable.

Cash paid (refunded) for interest and income taxes was as follows:

(Stated in millions)

	2017			2016		2015
Interest	$	572		$	599	$	346
Income tax	$	(44	)	$	750	$	1,567

Interest and other income includes the following:

(Stated in millions)

	2017		2016		2015
Interest income	$	128	$	110	$	52
Earnings of equity method investments		96		90		184
	$	224	$	200	$	236

The change in Allowance for doubtful accounts is as follows:

(Stated in millions)

	2017			2016			2015
Balance at beginning of year	$	397		$	333		$	275
Additions		7			123			75
Amounts written off		(163	)		(59	)		(17	)
Balance at end of year	$	241		$	397		$	333

Revenue in excess of billings related to contracts accounted for under the percentage-of-completion method was $0.3 billion and $0.5 billion at December 31, 2017 and 2016, respectively.

Accounts payable and accrued liabilities are summarized as follows:

(Stated in millions)

	2017		2016
Payroll, vacation and employee benefits	$	1,296	$	1,349
Trade		4,614		4,004
Deferred revenue		752		1,088
Other		3,374		3,575
	$	10,036	$	10,016