Use a consistent unit
Count either individual items or batches, then measure the total active human minutes for that same unit. Mixing a per-item count with a per-batch time can make an estimate wildly misleading.
Calculate the baseline
Weekly workload equals weekly occurrences multiplied by minutes per occurrence, divided by 60. Convert monthly volume using 52 weeks divided by 12 months. Avoid multiplying again by team headcount when minutes already include everyone’s work.
Subtract the new work
Net released time equals baseline effort times an assumed reduction percentage, minus review and maintenance. The result can be negative. An honest estimate should make that outcome visible rather than clipping it to zero.
Keep time and money separate
Recovered hours are capacity, not automatically cash savings. Only calculate financial returns with a stated cost basis, implementation effort, subscription costs, and a realistic view of how the released capacity will be used.
Use a range of editable assumptions until a real pilot produces evidence.