What’s an error bar? What does it have to do with Google Sheets? You can put error bars onto bar graphs you make with Google Sheets because it’s one of the features available on the Chart editor’s “Customize” tab under “Series”.
We’ll cover how to add error bars in google sheets down below, but we have to first define what an error bar is in the first place to proceed.
What is an Error Bar?
You’ve probably heard of “standard deviation” when it comes to making predictions or forecasts, right? Error bars graphically represent things of that nature. They represent data variability, from needing to round-off numbers to errors in gathering or representing the data.
- What Are They for? They give you a graphical representation or a general idea of how precise the measurement or data is, giving allowances for variances or the nature of rounding off numbers, which could result in errors or variance in forecasts.
- A Graphical Disclaimer: No matter how accurate you want your data to come across, there will be errors or variances in representation and results, particularly when making forecasts or predictions, like the results of a presidential election.
- The Margin of Error: The error bar offers viewers of your graph the potential data variance or “margin of error” you’re working with, which indicates the uncertainty or error of a reported measurement. This is especially true of big numbers, estimates, or ballpark figures.
This graphical margin of error applies to both estimated measurements and to extrapolated data in light of other factors skewing the theoretical outcome.
How to Add Error Bars in Google Sheets
Step 1: Open an existing spreadsheet or click this link to make a new spreadsheet. I’m opting to open a spreadsheet with existing data because this tutorial is about adding error bars into bar graphs.
Step 2: Double-click the chart in order to open the “Chart editor” side panel or sidebar.
Step 3: Scroll down the “Series” tab and select the “Error bars” checkbox. It’s below the “Trend line” and “Data labels” checkboxes.
The “Error bars” checkbox used to be below the “Trend line” checkbox, but Google Sheets ahs probably updated the user interface yet again at the time of this writing.
Types of Error Bars
There are three types of error bars. Technically four, but the fourth option is just “No error bars”, which isn’t really a type of error bar.
The left dropdown menu allows you to toggle between types while the left box is where you change the values of the error bars.
1. Percent
The first type of error bars we’ve added in the example above is the Percent error bar. This type of bar requires you to specify a percent or percentage value when making the bars. For instance, we’ve specified the default 10 percent.
This then shows you the upper and lower value of your error margin. The measurement could be from 90 percent to 110 percent in variation for every value, from TESLA to Amazon.
2. Constant
As for the constant error bar type, this shows error bars with a fixed value. Since we’re dealing with the revenues of the biggest corporations on the planet that number by the trillions altogether, we should use a large number as the constant.
It’s constant because, for instance, by specifying “25,000,000,000” as the value, it will show the error bar range in the +/- 25 billion value for every column bar in the form of lines cutting through the top of the bars or columns.
In the example above, the error bar is +/- 25 billion for every column regardless of how low or high the value of the column is.
3. Standard Deviation
Last but not least is standard deviation. Error bars of this type are put at the chart’s center instead of the top of every column compared to constant and percent error bars.
The standard deviation for this chart is about 5, hence the extreme look of the chart wherein the deviation is greater than the columns. Let’s try out something more reasonable, like 0.1.
The deviation error bars even fly off the chart but regardless, they come at the center. This is because standard deviation is the quantity calculated to indicate the extent of deviation for a group as a whole. It also shows how dispersed the data could become relative to the mean.
In other words, this error bar type tells you the variation or margin of error there is from the mean or the average.
What Else You Need to Find Out
Adding error bars to your graph couldn’t be simpler. First, make sure the graph is in column graph form or any form where you can easily see and decipher the error bars. From there, double-click the graph, go to the “Customize” tab, and then click on “Series”.
Right above “Trend line” (another predictive method used for identifying trends with its own standard deviations in place) and “Data labels”, there should also be a checkbox for “Error bars”. Just click on that and add a percentage of error there as you see fit for your data.
Now that you know how to add error bars, you can be a more proficient Google Sheets user!
References:
- Science Class Online, “Error Bars Using Google Sheets“, YouTube, January 23, 2016
- “Add data labels, notes, or error bars to a chart“, Google.com Support, Retrieved July 2, 2022
- “How to Add Error Bars in Google Sheets (in a few seconds)“, SpreadsheetPoint.com, June 26, 2022
- Amy Dykstra, “Using Google Sheets to make a bar graph with custom error bars“, YouTube, October 4, 2020
- Piers Support, “Adding Custom Error Bars to Column Graphs in Google Sheets“, YouTube, September 22, 2019
Google Sheet: make a copy