Microsoft Office Tutorials and References

In Depth Information

**Formatting or modifying error bars**

Figure 5-21 shows an XY chart that displays Y error bars using the Standard

Deviation option. Unlike other error bar options, error bars that use the Standard

Deviation option are displayed relative to the average of the data values. In this

example, the 100 data points have a mean of 11.67 and a standard deviation of

4.69. Therefore, the error bars display the mean, plus or minus 4.69. Using error

bars in this chart makes it clear that the majority of the data points fall within one

standard deviation of the mean.

Because the x values for this chart are consecutive values, the data points

(and the error bars) are equally spaced in the horizontal direction. This

spacing creates a useful banding effect.

Figure 5-21: This chart uses error bars that indicate the standard deviation.

Figure 5-22 shows an XY chart that uses both Y error bars and X error bars.

Both sets of error bars display the corresponding value plus or minus 10 percent.

The X error bars and Y error bars are independent of each other and can use

different options.

Formatting or modifying error bars

To change the formatting of error bars, double-click any error bar to display the

Format Error Bars dialog box. In terms of formatting, you can change the line style

and adjust the marker style (either on or off).