The chart lesson’s rule stands: bar, line, scatter and the occasional stacked bar cover 95% of honest working life, and exotic charts are usually a sentence that hasn’t been thought through. This lesson is about the other 5% — three specialist types with a genuine sentence of their own, plus the craft that stops each becoming decoration.
Waterfall: “how did we get from A to B?”
Some sentences are journeys: opening profit, plus this, minus that, equals closing profit. Bars can’t say it — they show states, not steps — and the waterfall exists precisely for it: each contribution floats as a rise or fall from where the last one ended, with anchored totals at the ends.
Insert → Waterfall, then the one setting everyone misses:
double-click each genuine total (opening, closing) and tick
Set as Total, so it drops to the axis instead of floating.
Where it earns its keep: profit bridges, budget-to-actual
explanations,
net-worth change over a year
(saved this, market did that, spent the other) — anywhere the
audience’s real question is “what happened between these two
numbers?”
Pareto: “which few causes are most of the problem?”
Complaint categories, defect types, spending buckets — count
them, and a familiar shape emerges: a vital few dominate. The
Pareto chart (Insert → Statistic Chart → Pareto, sibling
of the histogram)
makes the case in one image:
sorted bars for the
counts, plus a cumulative-percent line — so you can say “the
top three categories are 78% of everything” and point.
It’s top-N thinking and running totals fused into one honest picture, and its natural habitat is the prioritisation meeting: not “here are eleven problems” but “here is where effort pays” — the 80/20 instinct with evidence attached.
Combo: two series that belong together but don’t share units
Revenue in pounds against margin in percent; units sold against
returns rate. One axis can’t hold both — and stretching one
series to share the other’s axis is
a lie by scaling. The
combo chart (Insert → Combo) gives each series its own
mark (columns for the money, a line for the rate) and, when
needed, a secondary axis.
That secondary axis is the sharpest tool in this lesson and the easiest to cut yourself on: two axes means the reader can’t compare heights between series, only shapes — and a mischievous axis range can manufacture any correlation you like. The honesty rules: only when units genuinely differ; label both axes loudly; start bars’ axis at zero as always; and if the sentence is really “these two move together”, consider the scatter plot, which says it without axis games.
The specialist’s rule
Same as the generalist’s, applied at a higher price point: say the sentence first. “We went from X to Y because…” → waterfall. “Three causes are most of it” → Pareto. “The rate tells a different story from the total” → combo. If the sentence isn’t one of those, the basic four were already enough — and a specialist chart without its sentence is just decoration with better vocabulary.
Three new tools, three specific sentences, one unchanged principle. The gallery didn’t get more honest — you got more precise.