The same table, a different story
One table can tell three different things. A column chart says “who is biggest”. A line chart says “how it went in time”. A pie says “how many percent of a whole”. The wrong chart type does not lie on purpose — but people understand it wrong.
Today you will not make one chart. You will make three from the same data and you will see why on grades you leave a column, on pocket money a line, and a pie only on a survey.
Three charts from one table
Open sheet 备注s. In A1:B5 prepare a small snack table:
| A | B | |
|---|---|---|
| 1 | Snack | Count |
| 2 | roll | 8 |
| 3 | apple | 5 |
| 4 | bar | 4 |
| 5 | nothing | 5 |
22 votes in total. Columns are headings, rows are data. An average does not belong here.
-
Select A1:B5. Insert → Chart → Column. Title:
Snack — class vote. Put the chart next to the table. -
Select A1:B5 again. Insert → Chart → Pie. Title:
Share of snacks from 22 votes. Compare with the column — the same numbers, a different feel. -
On sheet
Pocketselect columns A1:C8 (Day, In, Spent). Insert a Line chart. Title:Spend by days. The line will show which day you spent most. -
On each chart click once on the title and rewrite it. Leave
Chart 2only on备注s, not in a hand-in.
A pie works only when the slices make a whole whole — here 22 votes = 100 %. Do not put a pie on grades. Grade 1 and grade 5 are not pieces of one pie, they are different subjects.
When which type
- Column — a comparison next to each other. Subjects, flavours, points. Default for most tables.
- Line — a time series. Days of the week, months, temperature by hours. Axis X must have an order (Mon, Tue, Wed…).
- Pie — shares of a whole, max five categories. More than five and it looks like a coloured pizza with no sense.
A line chart from five subjects (Maths, Czech…) looks like grades “go in time”. They do not. Subjects are not a calendar. On grades leave a column.
What often goes wrong
A pie with six slices. The fifth and sixth slice hide under each other. Either a column, or merge categories.
A line without a zero axis. Someone turns off “start at zero” and a small difference looks like a crash. With money leave the axis from zero.
Three charts, one extra range. If into A1:B5 you accidentally take the Total row too, the pie shows a fourth “slice” that is the sum of the others. It lies twice.
🏫 Grade average — column
On Grades you have A1:B6. A column chart, title Grades — March. Do not take the average in B8 into the chart. The column shows which subject is worst — not average 1.8 as a sixth column.
💰 Pocket money — a line
Column C (Spent) across seven days as a line chart. Do you see a spike on Wednesday? That is the day you spent more than usual. A column would show it too, but a line better says “the course of the week”.
📊 Class survey — pie or column
With 22 votes and four answers try both types next to each other. A pie shows shares, a column shows absolute counts. Into a report put the one where a teacher at once sees what won — usually a column with numbers on axis Y.
🏆 Mini dashboard — one chart
On the dashboard later leave one chart — a column from grades or from the survey. Three types next to each other would confuse. Picking a type is a decision: what do you want to say at a glance?
Now you 💪
First: a snack table on 备注s, column + pie, both named.
Second: a line from Pocket — spend by days. Change one spend and watch how the line moved.
Check: You know why grades = a column, days = a line, shares = a pie. No chart has the name Chart 1. The average is not in the data range.
What to take from this lesson
- Column = comparison. Line = time. Pie = shares of a whole.
- The same data, another chart = another story. Pick the type by the question.
- A pie max five categories. Leave it off grades.
© 2026 Ing. Martin Polak / AlgoRhino · 内容使用条款