Monitoring and drift
The forecast, pinned. The months, laid on it.
The day monitoring starts, the model's own baseline is pinned: twenty four months of revenue, customers, cash, margin, profit, headcount, churn and cost, each with its ten to ninety band. Every month's real figures are laid against it. A month outside the band is flagged. Two in a row on the same side is drift, and the monitor names the ledger row most likely behind it.
Build a twinPost actuals automatically
The pinned forecast never moves by itself. It is what the model said then, which is the only honest thing to measure against.
The loop
Paste a month, read the verdict, fix the number
- 01
Add a month, or a year
Paste a table with a header row, month first and any of eight figures after it in any order, or drop the CSV a finance system exports. Percentages are read as percentages. Or post it every month from that system with a key, and nobody has to remember.
- 02
The band is pinned at the first month
The first month with actuals is month zero of the forecast. The model runs its baseline from the ledger as it stands, a hundred times, and keeps the band. Re-pinning is a deliberate act with a button and a warning, because a forecast that moves to meet the actuals is not a forecast.
- 03
Every metric gets a card
The band, the middle, the months as dots coloured by whether they landed inside, one sentence saying what it means, and the state: on track, watch, or drifting.
- 04
The suspect is named
Revenue below the band with customers on track points at revenue per account. Fewer customers than expected points at churn. Cash short with profit on track points at operating cost. The monitor names the row, shows what the ledger says, what the actuals imply, and offers to move it. The move is recorded with a note saying why.
Measured
What the monitor watches
- Figures
- 8revenue, customers, cash, margin, profit, headcount, churn, cost
- Months ahead
- 24of pinned band, on the plan's horizon
- To call drift
- 2months in a row outside the band on the same side
- Column names it reads
- 40sales, turnover, MRR, accounts, FTE, gross margin, and the rest
Drift, not noise
One bad month is a bad month. Two on the same side is the model being wrong.
A ten to ninety band expects one month in five to fall outside it, so a single miss is reported and nothing more. The monitor calls drift when two months in a row land outside on the same side, or when more than half of three or more months do. That rule is written down here because a monitor that cries wolf gets switched off.
When it does call drift, it says by how much: the average distance of the actuals from the middle of the band, in percent, and the direction. That number is what the recalibration offer is computed from.
The tripwires from a brief are judged here too. A tripwire is a month and a figure; once that month has an actual, the wire has either tripped or held, and the monitor lists which.
Practical