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Appendix G: Using Excel to Create a Graph with Error Bars

You can use Excel to create graphs and add error bars, labels, trendlines, etc. To create a simple scatter plot with error bars follow these steps.

Creating a graph

1
Enter your data in an Excel spreadsheet as shown in Fig. 1.
Figure 1

Figure 1: Entering your data

2
Label your columns with names and units.
3
Highlight the data that you want to graph, as shown in Fig. 2.
Figure 2

Figure 2: Highlighting data to be graphed

4
Click the Insert tab at the top left of the Excel window (or click the chart icon in the horizontal tool bar).
  • Click the "Scatter" icon.
  • Click the picture of a graph with just the points (no lines) as shown in Fig. 3.
Figure 3

Figure 3: Choosing your graph

5
Your graph should appear as seen in Fig. 4.
Figure 4

Figure 4: Inserting your graph

Adding error bars

6
To add error bars, right click one of the points in the graph.
  • Select "format data series."
  • A window as shown in Fig. 5 will appear.
Figure 5

Figure 5: Error bar menu

7
Click on the 'Y Error Bars' tab if it is not already selected.
  • Click 'Both' for display option and 'Custom' for error amount.
  • The cursor will automatically appear in the '+' next to 'Custom'.
  • Select cells C2 through C7 and you will see these cells listed in the '+' box for the positive errors for each data point. See Fig. 6.
Figure 6

Figure 6: Entering values for error bars

8
Select the '–' error bar box and once again select cells C2 through C7.
  • Click 'OK' to complete this step.
  • Your graph will now have error bars as shown in Fig. 7.
Figure 7

Figure 7: Graph with error bars added