The asset retirement obligations liabilities (ARO) recognized by the Company are related to the estimated costs to dismantle and abandon its producing oil and natural gas properties and related equipment.

A reconciliation of the beginning and ending aggregate carrying amount of the ARO for the six-month periods ended June 30, 2025 and 2024 are shown in the following table.


(Thousands of dollars)	June 30, 2025		June 30, 2024
Balance at beginning of year	$	1,008,884	$	914,763
Accretion	28,477		25,827
Liabilities incurred	5,428		14,199

Revisions of previous estimates	3,999		1,995
Liabilities settled	(6,359)		(2,925)



Changes due to translation of foreign currencies	9,784		(4,541)
Balance at end of period	1,050,213		949,318
Current portion of liability	(70,104)		(25,622)
Non-current portion of liability	$	980,109	$	923,696

The estimation of future ARO is based on a number of assumptions requiring professional judgment. The Company cannot predict the type of revisions to these assumptions that may be required in future periods due to the availability of additional information such as: prices for oil field services, technological changes, governmental requirements and other factors.