Fallback Capacity Ratio
Manual daily capacity divided by daily volume. Multiply the throughput one trained person achieved before automation by the number of people who have actually done the work by hand, then divide by the volume the process handles per day. Below 1.0 the manual fallback cannot keep pace with incoming work.
What it is. A single number describing whether the manual fallback for an automated process can still absorb the work.
Per-person manual throughput, multiplied by capable headcount, divided by daily volume.
When to run it. Before approving an automation business case, and again on any process automated more than two years ago. It is most useful in the room where the case is decided, because that is the room the number is currently missing from.
How to run it.
Daily volume. Units per day through the process, in whatever unit the process uses.
Per-person manual throughput. Units one trained person completed per day before the deployment. This figure usually exists, because it was in the business case that funded the project.
Capable headcount. People who have actually done the work by hand. Names and dates, not the org chart for that function.
Multiply 2 by 3. Divide by 1.
Reading the answer. At 1.0 the fallback keeps pace. Above 1.0 it absorbs the work. Below 1.0 backlog grows for every day the automated process is unavailable. Materially below 1.0, the continuity plan describes a state the organization cannot reach.
Run it twice. The first pass assumes the remaining people are as good as they were. The second pass uses an honest estimate of people who have spent three years reviewing output rather than producing it. The gap between the two answers is the part no continuity plan currently records.
What a bad answer looks like. A ratio computed from the org chart rather than from names and dates. A per-person throughput taken from the automated process rather than the manual one. A ratio quoted to two decimal places, which suggests the inputs were estimated rather than found. And a ratio above 1.0 produced by counting people who have not done the work in years.
What to do with it. Say it out loud in the approval. The ratio is not a forecast and does not need to be precise. It needs to occupy a seat in the room that is currently empty, so the trade being made is visible to the people making it.