In order to determine net cash provided by operating activities, net loss is adjusted by, among other things, changes in current assets and current liabilities as follows (in millions):


	Six Months Ended June 30,
	2021		2020
Decrease (increase) in current assets:
Receivables, net	$	(3,069)	$	4,177
Inventories	(47)		1,136

Prepaid expenses and other	(103)		56
Increase (decrease) in current liabilities:
Accounts payable	3,979		(5,446)
Accrued expenses	284		(73)
Taxes other than income taxes payable	162		(180)
Income taxes payable	45		(148)
Changes in current assets and current liabilities	$	1,251	$	(478)

Changes in current assets and current liabilities for the six months ended June 30, 2021 were primarily due to the following:

•the increase in receivables was primarily due to an increase in commodity prices in June 2021 compared to December 2020 combined with an increase in sales volumes, partially offset by a decrease in income taxes receivable associated with the receipt of a $962 million refund related to our U.S federal income tax return for 2020; and

•the increase in accounts payable was due to an increase in commodity prices in June 2021 compared to December 2020 combined with an increase in crude oil and other feedstock volumes purchased.

Changes in current assets and current liabilities for the six months ended June 30, 2020 were primarily due to the following:

•the decrease in receivables was due to (i) a decrease of $4.1 billion as a result of a decrease in commodity prices in June 2020 compared to December 2019 combined with a decrease in sales volumes and (ii) the collection of $449 million for a blender’s tax credit receivable attributable to volumes blended during 2019 and 2018, partially offset by the recognition of an income tax receivable of approximately $440 million;

•the decrease in inventories was due to lower inventory levels combined with a decrease in commodity prices in June 2020 compared to December 2019; and

•the decrease in accounts payable was due to a decrease in commodity prices in June 2020 compared to December 2019 combined with a decrease in crude oil and other feedstock volumes purchased.


	Six Months Ended June 30,
	2021		2020
Interest paid in excess of amount capitalized, including interest on finance leases	$	290	$	250
Income taxes paid (refunded), net	(882)		76

Supplemental cash flow information related to our operating and finance leases was as follows (in millions):


	Six Months Ended June 30,
	2021				2020
	Operating Leases		Finance Leases		Operating Leases		Finance Leases
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows	$	199	$	35	$	216	$	48

Financing cash flows	—		63		—		32
Changes in lease balances resulting from new and modified leases (a)	315		46		163		1,495

(a)Noncash activity for the six months ended June 30, 2020 primarily included $1.4 billion for a finance lease right-of-use asset and related liability recognized in connection with the terminaling agreement with MVP.

There were no significant noncash investing and financing activities during the six months ended June 30, 2021 and 2020, except as noted in the table above.