The Chart That Misrepresents the Sales Trend
A manager has quarterly sales: Q1 100, Q2 105, Q3 108, Q4 160. They insert a column chart, then set the vertical axis minimum to 90 (instead of 0) so the differences 'show up better'. The chart now makes Q4 look roughly three times Q1. They also add a 3-D effect and a legend showing a single series named 'Sales'. A colleague is about to present this chart to the board as evidence of a dramatic turnaround.
1. Assess whether the chart is acceptable and identify the specific distortions.
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The chart is misleading. Truncating the value axis at 90 exaggerates differences: Q4 (160) vs Q1 (100) is a 60% rise, but on a 90–160 axis Q4's bar appears about 3× Q1's. The 3-D effect adds further false depth and can obscure bar heights. A single-series legend is redundant. For an honest comparison the axis should start at 0, the 3-D effect removed, and the legend dropped (or the series labelled directly). The judgement: a chart that changes the axis origin to 'show differences better' is changing the story, not the display.
2. Recommend a corrected chart and one alternative that communicates the trend fairly.
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Set the value axis minimum back to 0, use a flat 2-D column or line chart, and title it accurately ('Quarterly Sales, Q1–Q4'). A line chart is often better for a trend across time. If the manager genuinely wants to emphasise growth, show a percentage-change series (e.g. Q4 vs Q1 = +60%) alongside the absolute values, rather than distorting the axis. Always state the axis range if a non-zero baseline is unavoidable (e.g. for financial data where zero is meaningless), so the audience is not deceived.