Short answer: the waterfall (bridge) chart shows how a starting number becomes an ending number through a sequence of positive and negative steps — each a floating bar. It answers “what drove the change,” not just “what changed.” In a brewery it’s the margin bridge (last year to this year, split into price, mix, cost and volume), the volume bridge, and budget variance. The one rule: the steps must reconcile — start plus every contribution equals the end, nothing hidden — or the bridge lies while looking precise.
Part of The Brewer’s Chart Field Guide. Where a bar chart compares, the waterfall explains a change.
When to reach for it
Reach for a waterfall when you need to explain how one total became another — the contributing steps, positive and negative, in sequence. It’s the chart that turns “margin moved” into “here’s exactly what moved it,” which is why finance lives in it.
Use case 1 — The margin bridge
Last year’s margin to this year’s, decomposed into price, mix, cost and volume effects. Each step shows a lever’s contribution, so the conversation moves from “margin’s down” to “cost ate the price gain” — the margin-bridge view every FP&A team needs.
Use case 2 — The volume bridge
Plan volume to actual, stepped by new accounts, lost accounts, rate-of-sale change and new SKUs. It turns a volume miss into an attributed story the commercial team can act on.
Use case 3 — Budget vs actual variance
Start at budget, step through each cost line’s over/under, land on actual. The waterfall makes the few big variances obvious and the noise small — far clearer than a variance table.
Where this breaks
It must reconcile — start plus steps must equal the end exactly; a bridge that doesn’t tie out looks precise and is wrong. Hidden buckets lie — a fat “other” step defeats the purpose; decompose it. Order matters for some effects — price/mix/volume splits depend on calculation order; state your method. Too many steps — a 15-step bridge is a wall; group small ones.
The bottom line
The waterfall explains how a total changed — margin, volume, budget — by stepping through the drivers, increases and decreases, from start to end. Make it reconcile exactly, avoid hidden buckets, and keep the steps few. It’s the finance team’s favourite for a reason: it answers why, not just what. Next: stage-to-stage drop-off, the funnel chart.
Frequently asked questions
What is a waterfall chart and when should a brewery use one? A waterfall (or bridge) chart shows how a starting value becomes an ending value through a sequence of positive and negative steps, each a floating bar. Breweries use it for a margin bridge (last year’s margin to this year’s, broken into price, mix, cost and volume effects), a volume bridge, or budget-vs-actual variance. It answers “what drove the change”, not just “what changed.”
What is the difference between a waterfall chart and a bar chart? A bar chart compares independent categories; a waterfall shows a connected sequence where each step starts where the last ended, building from a start total to an end total. Use a bar chart to rank things, a waterfall to decompose a change — to explain why this quarter’s margin is up or down versus last.
How do you keep a waterfall chart honest? The steps must actually reconcile — start plus all the positive and negative contributions must equal the end total, with nothing hidden in an “other” bucket. Order the steps logically, colour increases and decreases consistently, and label each step’s value. A bridge that doesn’t tie out is worse than no chart, because it looks precise while being wrong.