Excel Line Graph: show a trend over time

A line graph shows how something changes over time — sales by month, weight by week. Dates or periods go along the bottom, the value goes up the side.

What you will make

Monthly sales as one line, then two lines to compare years.

Steps

1. Months in column A, sales in column B, with headings in row 1.
2. Select A1:B13.
3. Insert › Charts › Line › choose Line with Markers.
4. Click the title and type a real one, e.g. Sales 2026.

Add a second line

Put last year’s numbers in column C with a heading. Right-click the chart › Select Data › Add. Series name: click C1. Series values: select C2:C13. OK. A legend appears automatically.

The axis starts at the wrong number

Excel sometimes starts the vertical axis at 100 instead of 0, exaggerating small changes. Click the axis numbers › Ctrl + 1 › Bounds › Minimum 0.

Show the numbers on the line

Click the chart › + button › tick Data Labels. Too crowded? Label only the last point: click the line, click the last marker once more, then add the label.

Check it worked

The highest number in column B should be the highest point on the line. Months should read left to right in calendar order.

Common mistakes

Months are treated as a value (a second line appears for “Month”). Your months are numbers 1–12. Type them as Jan, Feb… or format the column as text.

Gaps in the line. A blank cell breaks the line. Right-click chart › Select Data › Hidden and Empty Cells › Connect data points with line.