OTHER ASSETS

12 Months Ended

Dec. 31, 2021

NOTE 9. OTHER ASSETS

Included in other assets were the following:


	December 31,
	2021		2020
	($ in millions)
Supply contracts	$	1,061.8	$	1,122.9
Other	70.0		68.4
Other assets	$	1,131.8	$	1,191.3

We have entered into various arrangements for the long-term supply of ethylene and electricity. A payment of $461.0 million was made during the second quarter of 2020 associated with a previously executed option to reserve additional ethylene at producer economics. The original liability was discounted and recorded at present value as of March 31, 2017. For the years ended December 31, 2020 and 2019, $4.0 million and $17.0 million, respectively, of interest expense was recorded for accretion of the 2020 payment liability discount.

During the year ended December 31, 2020, a payment of $75.8 million was made associated with the resolution of a dispute over the allocation to Olin of certain capital costs incurred at our Plaquemine, LA site.

The weighted-average useful life of long-term supply contracts at December 31, 2021 was 20 years. For the years ended December 31, 2021, 2020 and 2019, amortization expense of $69.4 million, $56.0 million and $39.9 million, respectively, was recognized within cost of goods sold related to our supply contracts and is reflected in depreciation and amortization on the consolidated statements of cash flows. We estimate that amortization expense will be approximately $70 million in 2022, 2023, 2024, 2025 and 2026 related to our long-term supply contracts. The long-term supply contracts are monitored for impairment each reporting period.

On January 1, 2019, we sold our 9.1% limited partnership interest in Bay Gas Storage Company, Ltd. (Bay Gas) for $20.0 million. The sale closed on February 7, 2019 which resulted in a gain of $11.2 million for the year ended December 31, 2019 which was recorded to other income in the consolidated statements of operations.