PROVISIONS

a) Provisions



	As at December 31, 2017		As at December 31, 2016
Environmental rehabilitation ("PER")		$2,944		$2,179
Post-retirement benefits	48		72
Share-based payments	37		34
Other employee benefits	27		45
Other	85		33
		$3,141		$2,363

b) Environmental Rehabilitation



	2017			2016
At January 1		$2,246			$1,982
PERs divested during the year	(31		)	—
Closed Sites
Impact of revisions to expected cash flows recorded in earnings	46			146
Settlements
Cash payments	(41		)	(28		)
Settlement gains	(1		)	(1		)
Accretion	12			10
Operating Sites
PERs arising in the year	836			134
Settlements
Cash payments	(18		)	(34		)
Settlement gains	(1		)	(3		)
Accretion	48			40
At December 31		$3,096			$2,246
Current portion (note 24)	(152		)	(67		)
		$2,944			$2,179

The eventual settlement of substantially all PERs is expected to take place between 2018 and 2058.

The PER has increased in the fourth quarter of 2017 by $864 million primarily due to changes in cost estimates at our Pascua-Lama, Lagunas Norte and Veladero properties, partially offset by changes in discount rates. For the year ended December 31, 2017, our PER balance increased by $850 million as a result of various impacts at our mine sites including new requirements related to water treatment, expanded footprints of our operations and updated estimates for reclamation activities. A 1% increase in the discount rate would result in a decrease in PER by $385 million and a 1% decrease in the discount rate would result in an increase in PER by $257 million, while holding the other assumptions constant.