Bridge / waterfall
Walk a number from start to end so the biggest hole is obvious.
Related: KPI / metric row
When to use
Use when a gap between two totals must be explained. Do not use for a time series (use annotated-chart). Do not use decorative 3D cylinders.
Guidelines
Start, steps, end. Down steps vs up steps use status tokens. Title names the largest hole.
Example
Same-day fill
Dwell, not scan quality, is the 12-point hole in same-day fill.
Bridge from theoretical fill to trailing fill
Start 93% to 81%; dwell is the hole. Steal labeled steps, not a 3D waterfall.
Rules
- Start and end totals are on the board.
- Each bar is a named driver with a signed delta.
- Title names the largest driver.
- Do not truncate the implicit axis to fake drama.
User recipe
Goal: explain a gap.
Inputs: start value, end value, drivers with signs.
Constraints: Bridge / waterfall Rules.
Prompt skeleton: “Make a bridge/waterfall slide in family consulting-exhibit using the Bridge / waterfall rules. Start: [n]. End: [n]. Drivers: [signed list].”
Anti-patterns
- Unlabeled bars.
- A waterfall that is actually a ranking of unrelated KPIs.