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


	Year Ended December 31,
	2023		2022		2021
Increase in current assets:
Receivables, net	$	(387)	$	(1,619)	$	(4,382)
Inventories	(684)		(672)		(253)

Prepaid expenses and other	(34)		(180)		(22)
Increase (decrease) in current liabilities:
Accounts payable	(169)		521		6,301
Accrued expenses	(50)		(5)		253
Taxes other than income taxes payable	(226)		98		104
Income taxes payable	(776)		231		224
Changes in current assets and current liabilities	$	(2,326)	$	(1,626)	$	2,225

Changes in current assets and current liabilities for the year ended December 31, 2023 were primarily due to the following:

•The increase in receivables was primarily due to an increase in refined petroleum product sales volumes in December 2023 compared to December 2022, partially offset by a decrease in related prices;

•The increase in inventories was primarily due to an increase in inventory volumes in December 2023 compared to December 2022;

•The decrease in accounts payable was due to a decrease in crude oil and other feedstock prices in December 2023 compared to December 2022, partially offset by an increase in related volumes purchased; and

•The decrease in income taxes payable was primarily due to income tax payments made during the year ended December 31, 2023.

Changes in current assets and current liabilities for the year ended December 31, 2022 were primarily due to the following:

•The increase in receivables was primarily due to an increase in refined petroleum product prices in December 2022 compared to December 2021;

•The increase in inventories was primarily due to an increase in inventory volumes associated with the DGD Port Arthur Plant, which commenced operations in the fourth quarter of 2022; and

•The increase in accounts payable was primarily due to an increase in feedstock volumes purchased for the start-up of the DGD Port Arthur Plant in December 2022 compared to December 2021.

Changes in current assets and current liabilities for the year ended December 31, 2021 were primarily due to the following:

•The increase in receivables was primarily due to an increase in refined petroleum product prices combined with an increase in sales volumes in December 2021 compared to December 2020, 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 primarily due to an increase in crude oil and other feedstock prices combined with an increase in related volumes purchased in December 2021 compared to December 2020.


	Year Ended December 31,
	2023		2022		2021
Interest paid in excess of amount capitalized, including interest on finance leases	$	562	$	570	$	598
Income taxes paid (refunded), net (see Note 15)	3,494		3,288		(842)

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


	Year Ended December 31,
	2023				2022				2021
	Operating Leases		Finance Leases		Operating Leases		Finance Leases		Operating Leases		Finance Leases
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows	$	428	$	107	$	395	$	83	$	397	$	72
Investing cash flows	—		—		—		—		1		—
Financing cash flows	—		250		—		180		—		135
Changes in lease balances resulting from new and modified leases (a)	396		157		178		660		451		378

(a)Noncash activity for the year ended December 31, 2022 primarily included approximately $500 million for a finance lease ROU asset and related liability recognized in connection with the completion of the DGD Port Arthur Plant described in Note 5.

There were no significant noncash investing and financing activities during the years ended December 31, 2023, 2022, and 2021, except as noted in the table above.