3.7 Describing data honestly in Excel
Your summary does not mislead the person reading it.
Before:02. Excel — Formulas & FunctionsUnlocks:05. Excel — Charts & Dashboards
Summarising data honestly means knowing when the mean lies and the median tells the truth, what a standard deviation is actually saying, and why a trendline through two correlated columns proves nothing about cause. This topic covers the describing side of statistics with Excel's functions, and it sits in the analysis module because pivots and charts constantly tempt you into summaries. The commonest confusion is false precision: eight decimal places on a rough estimate looks scientific and misleads, so rounding and significant figures get their own attention.
Work through these
Mean, median, mode, standard deviation and when the mean lies
The average, the middle value and the most common value describe different things. Reporting only the first can be actively misleading when the data is skewed. Knowing when that happens is the point of this item.
Quartiles, percentiles and outliers
Quartiles and percentiles describe the spread rather than the centre, and they are how unusual values get identified rather than argued about. Outliers deserve a decision, not silent removal.
Correlation, trendlines and the causation warning
A correlation says two things move together and says nothing about one causing the other, and a trendline drawn through anything will look convincing. This item is the standing warning.
Rounding, significant figures and false precision
Reporting a figure to more decimal places than your data supports implies a precision you do not have. Rounding honestly is part of describing data honestly.
Practice file
- xl-05-pivot-sales.xlsx
800 rows of fictional sales data for PivotTables, grouping, % of total and a first measure.
Opens in Excel. Every name, number and address in these files is made up. No account needed to download.
Sign in to keep your progress.
Free resources
We haven't checked most of these for screen reader use yet.
Links last checked 29 Aug 2026.
Stuck here?
Ask a mentor. A real person answers, and they can see exactly which topic you're on. Usually within a couple of working days.
Checking your session…
Topics shown in module order.