Just in case it helps anyone, I thought I would put the calculation in terms that are far easier to understand than anything else I've read today. The OK Subtraction is calculated as follows: 

Total cost of assets placed in Service - amount of federal bonus depreciation = the remaining basis for depreciation to be taken in subsequent years. That amount less the amount of current year depreciation expense equals the Ok depreciation adjustment. 

For example: 

Total cost of Items placed in service: $24,989

Total Federal 2023 bonus Depreciation: $19,991 (80% of $24,989)

Basis for Depreciation to be taken in subsequent years: $4,998 ($24,989 – $19,991)

Less 2023 current depreciation deduction: $(178)

Total Oklahoma Bonus Depreciation Adjustment: $4,820

An OK worksheet sure would be nice!!