STOCK-BASED COMPENSATION (Tables)

3 Months Ended

Mar. 31, 2025

Share-Based Payment Arrangement [Abstract]

Stock-based compensation expense

Stock-based compensation expense was as follows:

	Three Months Ended March 31,
	2025		2024
Stock Compensation Expense	($ in millions)
Stock-based compensation	$	5.3	$	5.6
Mark-to-market adjustments	(3.8)		2.2
Total expense	$	1.5	$	7.8

Schedule of fair value of performance share awards granted valuation assumptions

The fair value of each performance share award based on TSR was estimated on the date of grant, using a Monte Carlo simulation model with the following weighted average assumptions:

Grant Date Assumptions - Performance Shares	2025			2024
Risk-free interest rate	4.27		%	4.53		%
Expected volatility of Olin common stock	37		%	41		%
Expected average volatility of peer companies	35		%	37		%
Average correlation coefficient of peer companies	0.45			0.40
Expected life (years)	3.0			3.0
Grant date fair value (TSR-based award)	$	27.46		$	72.80
Grant date fair value (net income-based award)	$	27.62		$	54.07
Performance share awards granted	545,572			180,714