Case interview charts and exhibits: a four-step way to read them

How to read charts, tables and exhibits in case interviews: a four-step method, the chart types that appear most, and the mistakes that cost offers. 5 min readUpdated 12 November 2026By the Prepper team

Most case interviews include at least one chart or table, and online tests such as McKinsey Solve and the BCG online case are built on them. The interviewer is not checking whether you can read a number. They want to know what the exhibit means for the client.

The four steps

Orient (10 seconds, aloud). "This table shows leavers by age group, as a share of leavers and of all customers."
Read. Title, axes, units, time period, footnotes. Most errors are a missed unit: thousands for millions, percent for percentage points.
Find the insight. Look for the largest value, the outlier, the change in trend, or the gap between two series.
Say the so-what. Link it to the case question and say what you would do next.

Example

Age group	Share of leavers	Share of all customers
Under 30	70%	15%
30 to 50	22%	40%
Over 50	8%	45%

Weak answer: "Seventy percent of leavers are under 30."

Strong answer: "Under-30s are 15% of customers but 70% of leavers, so they leave far more often than anyone else, while over-50s hardly move. A price cut for everyone would mostly reward customers who were staying anyway. I would aim the response at under-30s and find out why they leave."

This exhibit comes from the bank competitive response case.

Chart types to know

Chart	What to look at
Stacked bar	The mix, and how it changes
Waterfall	Which steps add and which subtract
Scatter	The trend and the outliers
Marimekko	Width is segment size, height is share
Line	Slope, turning points, gaps between lines
Two-axis chart	Which series uses which axis

Mistakes

Describing the chart without a conclusion.
Calculating before deciding what you are looking for.
Staying silent for a minute. Say what you are doing.

Frequently asked questions

How long should I take to read an exhibit in a case interview?
About 30 seconds in silence is fine if you first say what the exhibit shows. Then give the insight and the so-what.
What is a so-what in a case interview?
The meaning of a finding for the client's decision: what it changes and what you would do next.
How do I get better at chart reading for consulting tests?
Practise timed exhibit questions and force yourself to write one sentence of insight for each chart before you look at the answer.

How long should I take to read an exhibit in a case interview?

About 30 seconds in silence is fine if you first say what the exhibit shows. Then give the insight and the so-what.

What is a so-what in a case interview?

The meaning of a finding for the client's decision: what it changes and what you would do next.

How do I get better at chart reading for consulting tests?

Practise timed exhibit questions and force yourself to write one sentence of insight for each chart before you look at the answer.