How do error bars work in Power BI?

What is Error Bars?
Error bars are agraphical way to visualize the uncertainty of data .
They give a general idea of how precise a measurement is, or conversely, how far from the reported value the true (error-free) value is.
Error bars help to identify estimated error or uncertainty to give a general sense of how precise measures are with data points.

Interpretation of Error Bars in Power BI Visuals?

We can add error bars to line charts to visualize the uncertainty in the data!

Uncertainty is one of the important aspects of data, where the displayed value of a point needs to be shown with the range of its possible values.

With this new feature, we can specify upper and lower bounds to the values in the line chart and customize the way the uncertainty of data is visualized in the chart.

In Power BI we need to enable this feature, which is a preview feature of March 2022, and make sure we go to File > Options > Preview Features and make sure the error bars checkbox is checked.

Also, please make sure we enable the ‘New format pane” feature, as “Error bars” functionality is available for the New format pane only. Then we can create a line chart and add a measure for which you have upper and lower bound fields to display.

Line chart

Below I am visualizing a line chart over time (date) with a profit metric and taking the segment as a legend with two categories.

Where to configure error bars in Power BI?

In the Analytics pane, we will see a new Error bars card.

At the top, we’ll see a dropdown to select the measure to which we would like to add error bars.

Beneath it, we’ll find options to enable error bars for this measure, add upper and lower bound fields, and indicate how the upper and lower bounds relate to the measure.

Absolute means that the fields contain the exact value of the upper or lower bound, while relative means that the fields contain the difference between the upper or lower bound and the measure.

For example, if at one point my measure has a value of 60, an upper bound of 90, and a lower bound of 45, my upper bound field in absolute terms would be 90 and my lower bound 45, while my upper bound in relative terms would be 30 while my lower bound would be -15. Choose the option that suits the format of your upper and lower bound fields.

Confidence interval with Error Bars

By default, these intervals will be represented by a vertical line with horizontal caps on either end.