How to Add Error Bars in Excel: Standard Deviation at Its Finest

No one wants to be wrong.  In fact, if we had the ability to be perfect all the time, we would.  But the truth is, many complicated tasks require the use of helpful tools to get us as close to that point of perfection with the least amount of error as possible. Running a successful business can be especially dependent on the information organized and synthesized by such tools. Once you’ve effortlessly become familiar with Excel through one of our online courses, such as the Excel Training Course for all skill levels, you will have working knowledge of the valuable features of the world’s most popular business software. One such feature includes adding error bars to any excel generated chart, a skill guaranteed to boost any Excel user’s confidence in the data provided for that particular chart.   

Error bars show potential error or degree of uncertainty relative to each data market in a series.

They allow you to quickly see any standard deviations or margins of error on your chart.  Excel allows you to show them as a standard error amount, a standard deviation or a percentage as well as determine the specific error amounts to be displayed.  You can use error bars in 2-D area, bar, column, line, xy (scatter), and bubble charts. In scatter and bubble charts, you can show error bars for x and y values.

Simply follow these rules to add error bars:

1.    Select a data series, Excel displays the Chart Tools, adding the Design and Format tabs:

2.    On the Design tab, in the Chart Layouts group, click the Add Chart Element icon and choose Error Bars list:

Excel offers several error bars. However, you can also use More Error Bars Options…. If necessary, you can fine-tune the error bar settings from the Format Error Bars task pane:

In the Format Error Bars task pane you can choose:

• Direction group:

  • Both Shows the actual data point value plus and minus a specific error amount

  • Minus Shows the actual data point value minus a specific error amount

  • Plus Shows the actual data point value plus a specific error amount

• End Style group:

  • No Cap Display error bars without end caps

  • Cap Displays error bars with end caps

• Error Amount group-Excel enables you to specify several types of error bars:

  • Fixed value uses the constant value that you specify in the Fixed value box to calculate the error amount for each data point and displays this error amount in the same height for Y error bars and the same width for X error bars.

  • Percentage uses the percentage that you specify in the Percentage box to calculate the error amount for each data point as a percentage of the value of that data point. Y error bars and X error bars that are based on the percentage of the value of the data points vary in size.

  • Standard deviation(s) displays the standard deviation for the plotted values that is calculated for each data point and then multiplied by the number that you specify in the Standard deviation(s) box. The resulting Y error bars or X error bars are the same size and do not vary with each data point.

  • Standard error displays the standard error amount for all plotted values. All data points in the series display the error amount in the same height for Y error bars and the same width for X error bars.

  • Custom uses values in a worksheet range that you specify as error amounts. Using this option, you can include formulas in the worksheet range when calculating the error amounts.

The direction of the error bars depends on the type of chart you’re using. Scatter charts can show both horizontal and vertical error bars. You can remove either of these error bars by selecting them, and then pressing Delete.

The ease with which our tutorials provide students with all the necessary information enables our students to efficiently and effectively get the most out of Excel, the world’s most popular software for any kind of business.

For more wonderfully useful information on Excel, be sure to read Excel Tips and Tricks: Use Excel Like a Pro and also enroll in the valuable courses below!

• Excel for Beginners

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