How to Interpret Charts and Data in Consulting Case Interviews

In case interviews, diagrams, and data are standard. As a prospective consultant, it should be natural to interpret them. Our expert Agrim explains in his article below exactly how you can convince your interviewer with your interpretation and what the most common mistakes are in the evaluation. In addition, you will get a step-by-step explanation of how the interpretation should look, so that you are perfectly prepared for your next case interview. This is clearly illustrated by means of an example.

1. What Is the Purpose of Having Charts and Data in a Case Interview?

In case interviews, candidates can receive information as exhibits – charts, graphs, infographics, and data tables. Before we learn how to interpret them, let us understand their purpose.

1.1 What Is the Purpose of Exhibits?

• Exhibits allow the interviewer to test the candidate’s ability to absorb a large amount of information and draw useful insights relevant to the case
• Exhibits allow the interviewer to also test the candidate’s resourcefulness, awareness, presence of mind, and ability to solve a problem with only the given information
• Exhibits convey a large amount of information to the candidate in a short time, without verbalizing it
• Exhibits contain quantitative and/or qualitative information to help the candidate in solving the case (fully or partially) and move forward in the right direction

1.2 What Is Not the Purpose of Exhibits?

• Exhibits do not necessarily mean to push the candidate toward doing math
• Exhibits do not necessarily mean to confuse the candidate with unnecessary information and send them on a wild goose chase

2. What Do Interviewers Want to Hear?

2.1 Case Prompt

With the purpose of exhibits sorted, let's understand what does an interviewer want to hear over an exhibit? We will learn through an example exhibit from a full case.

You can access the full case on PrepLounge Premium here. The case has 5 exhibits and a 38-min video solution explaining everything in detail.

• Case context: Our client is the CEO of BoxxFitness - a leading gym chain in the US with over 1,500 gyms. BoxxFitness is a premium gym concept with an annual membership fee that is 2-3x higher than most mainstream gyms. Each gym has a limited number of membership slots. Each member gets a dedicated locker, unlimited personal training, unlimited classes, and unlimited equipment usage.
• Case problem: In the last 3 years the chain has seen a decline in its profit margin
• Case question: Can you identify the potential reasons for this decline?

2.2 Example Exhibit: US Gym Market Revenue in §Bn

So what do interviewers really want to hear? Well, basically 3 things – observations, insights, and implications. Let us look at them in detail:

Level 1: Observations

These are basic factual & descriptive observations from the exhibit. They should cover the case context and the exhibit facts and are a necessary hygiene check in the interpretation process. They indicate to the interviewer that you are able to read & understand exhibits.

Some samples of Level 1 statements based on the above exhibit include:

• What is the exhibit about? e.g. “This graph tells us the last 5 years of historical revenue for the US Gym market (case context) in billions of US dollars, split across 4 price-based market segments (case context, exhibit facts)”
• What is happening in the graph overall? e.g. “Overall industry is growing by approx. 8% per year in the last 5 years (exhibit facts)”
• Other high-level details: “Luxury segment is doubling in last 5 years from $2Bn to $4Bn” (exhibit facts), “Mainstream segment is growing by the largest amount ($7Bn) in 5 years” (exhibit facts)

Level 2: Insights and Inferences

These are second-order derivations moving beyond the level 1 observations. The insights establish relations between different data points in the exhibit. They indicate to the interviewer that you are able to link multiple data points in the exhibit and synthesize something that may not be immediately obvious.

Level 2 will require you to sometimes do basic mental math (such as calculating year-over-year growth, fractions, percentages, totals, etc.) While Level 1 is based on only the exhibit, Level 2 brings the client and the client’s problem into focus by connecting data points. Some samples of Level 2 based on the above exhibit include:

• What are some specific trends/patterns? e.g. “Premium segment (focus on the client) is growing slower (case context) than other segments at nearly 5% per year (exhibit facts)”
• What are the outcomes of these trends? e.g.“Premium segment’s share (focus on the client) has shrunk from 23% to 20% (exhibit facts) due to this slower growth (case context)”

Level 3: Implication and Solution

Level 3 is the most important ingredient to your success with exhibits. It is also not an easy ability to master. There is no fixed recipe or checklist for Level 3, but a candidate can develop this ability with practice and guidance from a competent coach on PrepLounge.

For Level 3, the candidate has to leverage their Level 1 & Level 2 statements, combine them with business acumen, and try to generate & solve hypotheses that address the case question and try to solve the case problem.

Some examples of Level 3 based on the above exhibit include the following:

• Sample 1: Since the premium segment is growing slowly (ref. Level 2), there might be some adversarial pressure on our client (hypothesis based on business acumen), thus affecting the profit margin (case problem). We could investigate further on how our client is performing within the segment to validate if this could be a valid reason for profit decline (case question)
• Sample 2: Faster growth rate of Luxury and Mainstream segments (ref. Level 1) indicates evolving customer preferences (business acumen). It seems that premium gym seekers are becoming increasingly divided and are either upgrading or downgrading (hypothesis based on business acumen). Let us try to validate if customer preferences are changing and leading to a profit decline (case problem) – do we have any information about it? (driving the case)
• Sample 3: If indeed customer preferences are changing for the worse (case problem), perhaps our client would like to explore these faster-growing segments (driving the case)

3. Mistakes by Candidates When Dealing With Exhibits

3.1 Basic Mistakes / Hygiene Checks

Not understanding the exhibit:

• Sometimes, parts of the exhibit may not be fully clear upfront. In such situations, many candidates never really clarify their doubts. They either assume some explanations of their own for the unclear bits or simply ignore them. Both ways are equally dangerous.
• So if you are unclear about something – please clarify it with the interviewer until you fully understand the exhibit.
• If you do not ask, the interviewer will assume that you have fully understood the exhibit and shall expect an analysis accordingly.
• This mistake indicates ineffective communication & presence – which is a key pillar in interview evaluation.

Errors in reading the exhibit:

• Candidates may misread chart elements such as legend, axes titles, chart title, axes values, units of measurement, and so on (e.g. market share vs share of wallet, cumulative customers vs new customers, etc.).
• Candidates may also misread the magnitude of the numbers (e.g. millions vs thousands).
• Further, candidates may misspeak some terms (e.g. dollars vs pounds, 2011 vs 2001, etc.) – either a slip of the tongue or nervousness.
• These mistakes indicate ineffective communication & presence and show that the candidate is not well prepared.

3.2 Technical Mistakes

Lack of Level 2 statements:

• If the candidate is not able to connect the dots and draw out advanced insights, it is a potential red flag.
• It shows poor insight generation skills – a key pillar in interview evaluation.

Lack of Level 3 statements:

• Having Level 3 statements can vastly and definitively increase your chances of success.
• It shows to the interviewer very clearly that you are reaching into the ‘so-what?’ of the problem.
• A lack of Level 3 statements shows poor problem-solving skills – a key pillar in interview evaluation.
• Demanding interviewers may even consider the lack of Level 3 a red flag or deal-breaker.

3.3 Process-Related Mistakes

Not driving the case forward / not being solution-oriented:

• In the live case example above we saw that part of the Level 3 statements were devoted to driving the case forward and moving toward the solution.
• This is very important not just for candidate-led cases, but also for interviewer-led cases. Because in real-life, all cases are run by the consultant. The consultant is supposed to find potential solutions to the problem, select the best solution, and propose it to the project manager. A consultant should not expect end-to-end guidance at every step and needs to be independent, resourceful, and always driving forward toward the solution.
• Hence, if the candidate does not show this drive, then it indicates poor practicality and effectiveness – a key pillar in interview evaluation.
• It leaves a bad mark on their skillset and shows they need more preparation.
• Demanding interviewers may even consider this a red flag or deal-breaker.

3.4 Communication Mistakes

Over-Communicating

• Some candidates like to launch a detailed commentary of every pixel they see on the exhibit. They feel it shows good exhibit reading skills.
• Such candidates end up exhausting their 2-3 minutes of exhibit interpretation time in only Level 1 and some Level 2 statements. They hardly ever get to Level 3.
• They also end up confusing the interviewer with observations that the interviewer does not need to hear.
• All this indicates poor communication & presence and poor practicality & effectiveness.

Under-Communicating

• Some candidates are on the other side of the spectrum – they don’t elucidate and verbalize enough.
• They may make some observations, but not say them out loud. Such candidates often say that they “thought about it” – but they didn’t say it.
• This includes even Level 2 and Level 3 statements.
• If you don’t say it out loud, the interviewer would not know that you observed it or thought about it, and hence the interviewer might mark you down on that bit.
• Consulting is a profession built on communication and under-communicating indicates poor communication & presence and poor practicality & effectiveness.

4. What to Do in an Interview?

We now understand what are the rights and wrongs when dealing with exhibits in a case interview. Let us now look at a checklist that can help you become better at it. This is a good starting point to follow for candidates who are struggling with exhibits. As you practice and become better, feel free to make it your own.

Step 1: You are presented with an exhibit [graph, chart, table, etc.]

Step 2: Relax and take a deep breath. Avoid feeling overwhelmed. Resist the urge to start speaking something immediately. Avoid trying to look at and process too many things at once.

Step 3: Ask the interviewer for a bit of time to “read and understand the exhibit”. There is no fixed time – 10, 20, 30 seconds – as much as you need, but don’t take an eternity.

Step 4: Observe Level 1 details one-by-one & carefully, and try to figure out what the exhibit is all about. The exhibit may not be precisely what you had asked the interviewer – so best to look at it afresh. You could and should look at the chart title, axis titles, axis scale, units of the quantities, legend, series titles, labels, and other such elements.

Step 5: Ask any questions, doubts, or clarifications about the exhibit that you may have.

Step 6: After clarifying your doubts, spend a few seconds thinking about how this exhibit helps you in solving the case, and then try to formulate Level 2 statements and try to figure out some Level 3 implications.

Step 7: Speak out Level 1 details to the interviewer. You don’t need to speak out about all of them – only those bits that you may find relevant to solving the case.

Step 8: Start speaking out Level 2 details – one by one-by-one. Again, use your better judgment in selecting which Level 2 details to observe and speak about. The best ones are those that are useful for solving the case and also lead up to your Level 3 details.

Step 9: Finally close out the exhibit reading by suggesting your chosen Level 3 statements. The statements may lead to a move forward in the case, could lead to another deep-dive exhibit, or could lead to the final solution of the case.

5. About the Author

Agrim

CoachingPlus Expert | 34 Reviews with 100% Recommendation Rate | Ex BCG and Opera Solutions | 131 meetings

• Professional Experience: BCG, Opera Solutions
• Languages: English
• Location: United Arab Emirates

Agrim is an interview coach, former BCG Project Leader, and Solutions Analyst at Opera Solutions. He is a Specialist in PEI / Fit / Unorthodox Cases / CV / Market Sizing. Agrim helped a lot of candidates to land offers from McKinsey, BCG, and Bain. He is an expert in the Middle East (Saudi Arabia / Dubai / Qatar / Abu Dhabi / Oman / Kuwait). As a consultant, Agrim worked as a Project Leader at BCG for 4 years. Before that, he was a Solutions Analyst for Opera Solutions for 2 years.