Deductions & credits

@AmyC Thank you. Consulting my 2015-2019 returns helped me rebuild the prior depreciation and I am now confident about that number BUT I still don't know what the number should be for Prior AMT depreciation.  Note, there were never any adjustments shown on the Alternative Minimum Tax Depreciation Reports for previous years.  Does that mean that the answer to Prior AMT Depreciation is zero, the same amount as Prior Depreciation or some other number (if so, how would I figure that)?