Small Multiple or trellising allows you to split a visual into multiple versions of itself, presented side-by-side, with its data partitioned across these versions by a chosen dimension.
Power BI has introduced a preview version of Small multiples feature in December 2020 update.
Currently, you can create small multiples on your bar/column, line, and area charts.
Lets see how to use Small Multiples chart in Power BI step by step.
Make sure you have installed a latest version( December 2020) of Power BI Desktop.
Enable Small Multiple Preview
In Ribbon bar, click on File tab, the select Options and Settings> Options
After that, in Options menu, click on Preview Features and check the Small multiples and click on OK button.
Once you done with the changes, you need to restart the Power BI desktop, as preview changes will reflect after restarting the Power BI Desktop, so just close and re-open Power BI desktop.
Here we are using a Financial Sample Dataset as shown below.
Creating a Small Multiples
Lets see how to create a small multiples for clustered column chart which will display a Sales by Month, Year, and segment across the country.
Lets take a clustered column chart into report page as shown below.
Now drag a following data fields into chart as shown below.
Once you done with this, you will see a simple clustered line chart is created which display the Sales by Month, Year and segment.
Lets create a small multiples for this chart which which will display a Sales by Month, Year, and segment across the country.
For this you need to drag a country field into small multiples fields pane as shown below.
Once you drag data fields in chart Fields pane, you will see that a small multiples chart is created and
split into a 2×2 grid (By default, that can be changed in format settings), where the data has been divided along Country dimension.
Chart axes are synchronized, with one Y axis at the left of each row and one X axis at the bottom of each column.
Also you can scroll down to see the rest data points, in case If you have more small multiples than fit into the grid.
As we can see only four countries data is showing on chart that is United state of America, Mexico, Germany, and France, while there is data for one more country that is Canada.
Lets scroll down to see country Canada data on chart.
Now you can see, country Canada data also.
You can also sort the Small multiples, click on ellipsis (…) there you can see a option Sort small , multiples, as shown below.
Formatting a Small multiples
You can change the dimensions of the grid in the Grid layout card, the default is a 2×2 grid of small multiples.
You can adjust the number of rows and columns to up to 6×6. If you have more small multiples than fit into the grid, that will load in as you scroll down.
Lets go to Format pane, click on Grid Layout as shown below.
Lets change the number of rows and columns to 3×1 that means three row and one column on grid.
Once you make changes, just take a look at chart. and you will see grid dimension is changed into 3 rows and one column as shown below.
You can also format the small multiple title such as customizing a font, color, alignment and text size.
Go to small multiple title option in format pane as shown below.