| name | codexkit-fpa-rolling-forecast |
| description | Build and maintain a rolling financial forecast using a 12–18 month horizon. Lock actuals, reforecast remaining periods, extend the planning window, and generate a waterfall bridge showing prior-to-new variance. Use monthly or quarterly when the organization follows a continuous planning cadence instead of annual budgets. |
| version | 1.0.0 |
| category | data |
Rolling Forecast Builder
When to Use
- Monthly or quarterly when updating financial projections
- When replacing static annual budgets with continuous planning
- When management needs a forward-looking 12–18 month view at all times
- When actuals deviate significantly and re-forecasting is required
Procedure
Step 1 — Lock Actuals
- Import actuals for completed periods from the ERP or accounting system
- Freeze these periods — no further edits allowed
- Calculate YTD variance vs prior forecast for each line item
Step 2 — Reforecast Remaining Periods
- For each P&L line, update the driver assumptions:
- Revenue: units × price, or pipeline × conversion rate
- COGS: volume × unit cost, or % of revenue
- OpEx: headcount × avg cost, or run-rate with known changes
- Apply known one-time items (restructuring, capex, etc.)
- Document every assumption change vs prior forecast
Step 3 — Extend Horizon
- Add new periods to maintain the 12–18 month rolling window
- Use trailing actuals + seasonality patterns to seed new periods
- Flag any new periods with lower confidence level
Step 4 — Sensitize Scenarios
- Apply Base / Bull / Bear assumptions to key drivers
- Show range around the forecast (not a single number)
Step 5 — Generate Waterfall Bridge
- Start with Prior Forecast for the full period
- Add variance buckets: Volume | Price/Mix | Timing | Cost | FX | One-offs
- Arrive at New Forecast
- Summarize the top 5 variance drivers in narrative form
Inputs
| Input | Required | Format |
|---|
| Actuals YTD | Yes | P&L by month |
| Prior forecast | Yes | P&L by month for forecast period |
| Driver assumptions updates | Yes | Line-by-line changes with rationale |
| Seasonality pattern | Recommended | Historical % distribution by month |
Output
## Rolling Forecast — [Period] Update
### P&L Summary (in $000s)
| Line | YTD Actual | Remaining Forecast | Full Year | vs Prior | Δ% |
|------|-----------|-------------------|-----------|---------|-----|
| Revenue | 12,400 | 19,200 | 31,600 | +1,600 | +5.3% |
| COGS | (5,200) | (8,100) | (13,300) | (400) | +3.1% |
| Gross Profit | 7,200 | 11,100 | 18,300 | +1,200 | +7.0% |
| OpEx | (4,800) | (7,600) | (12,400) | (200) | +1.6% |
| EBITDA | 2,400 | 3,500 | 5,900 | +1,000 | +20.4% |
### Waterfall Bridge (Revenue)
Prior Forecast: $30,000
+ Volume: +$800 (higher unit sales in Q3)
+ Price/Mix: +$500 (premium tier adoption)
+ Timing: +$300 (deal pulled forward)
= New Forecast: $31,600
### Assumption Log
| Driver | Prior | New | Rationale |
|--------|-------|-----|-----------|
| Q3 unit sales | 1,200 | 1,350 | Pipeline confirmed |
| Premium mix | 15% | 18% | Q2 trend extrapolated |
| Headcount | 45 | 47 | 2 new hires approved |
### Confidence Level: HIGH (months 1–6) / MEDIUM (months 7–12) / LOW (months 13–18)
Definition of Done
Examples
Prompt
We are in Month 6 of FY2026. Here are our YTD actuals: [paste P&L]
Prior forecast for the full year was: [paste prior forecast]
Key changes: Q3 pipeline is 15% stronger, we approved 2 new hires, raw material cost increased 3%.
Generate a rolling forecast update with waterfall bridge.
Quality Criteria
Verification (4C)
| Check | Question |
|---|
| Correctness | Are formulas, aggregations, and statistical methods applied correctly? |
| Completeness | Does the analysis cover all requested metrics and time ranges? |
| Context-fit | Are the chosen metrics relevant to the business question being answered? |
| Consequence | If this data were used for a decision today, what blind spots remain? |
Edge Cases
- Missing or incomplete data — Document gaps and their potential impact on conclusions. Provide ranges instead of point estimates.
- Outliers skewing results — Report with and without outliers. Document the decision to include or exclude.
- Changing data definitions mid-period — Split analysis at the change boundary and note the schema difference.
Changelog