Start with the headline, not the process. Tell the interviewer the most important conclusion you see, then support it with the two or three data points that make the conclusion credible.
A weak exhibit answer often follows the order of the chart: first this bar, then that bar, then another number. A stronger answer reorganizes the data around the business message. The interviewer already has the chart; they need your interpretation.
After the evidence, add the implication. Explain what the pattern means for the client or which part of the case you would investigate next.
A useful format is conclusion, evidence, implication. It keeps the answer short while still showing that you read the exhibit carefully.