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Create dynamic format strings for measures

APPLIES TO: Power BI Desktop  Power BI service

With dynamic format strings for measures, you can determine how measures appear in visuals by conditionally applying a format string with a separate DAX expression.

Note

Dynamic format strings for measures is currently in Preview. When in Preview, functionality and documentation are likely to change.

Dynamic format strings overcome an inherent disadvantage of using the FORMAT function. That is, with FORMAT even numeric data types are returned as a string, which may not work with visuals that require numeric values, like charts. When using dynamic format strings, the measure keeps its data type and isn't forced to change to a string data type. This applies different format strings to the measure depending on the context.

Dynamic format strings can also be used with calculation groups. The same DAX patterns that work with calculation groups can also be utilized in dynamic format strings for measures, but the scope is limited to individual measures instead of all measures in the model. To learn more, see Calculation groups - Dynamic format strings.

Create dynamic format strings

To create a dynamic format string

  1. In the Data pane, select the measure for which you want to specify a dynamic format string.

  2. In the Measure tools ribbon > Formatting section > Format listbox, select Dynamic. A new listbox with Format already selected appears to the left of the DAX formula bar. This drop down is how you can switch between the static measure DAX expression and the dynamic format string DAX expression. Whatever the static format string was in use before switching to Dynamic is prepopulated as a string in the DAX formula bar.

    Screenshot of Format dropdown.

  3. Overwrite the string with a DAX expression that outputs the correct format string for your measure. For example, the following expression looks up the currency format string we want from a ‘Country Currency Format Strings’ table:

    Screenshot of Dynamic format measure expression.

  4. Verify your dynamic format string works in a visual.

    To delete the dynamic format string and return to using a static format string, in the Formatting section > Format listbox, select a different format option. Because there's no undo to this action, a dialog appears asking if you want to proceed. If you want to go back to using a dynamic format string again, you must reenter the DAX expression.

    Screenshot of Format change warning.

Example

The best way to learn about a new feature is to try it yourself. You can do just that with the sample Adventure Works 2020 PBIX file available at DAX sample model. By using the sample model, you can add currency conversion to show converted sales amount by year. After downloading, open the file in Power BI Desktop.

Create new tables

The sample model doesn't contain all the data necessary to create and use dynamic format strings. To get started, you first need to add two tables.

  1. On the Home ribbon, select Enter data.

  2. In the Create Table dialog, enter the following table name, and then copy and paste the following table:

    Table name: Country Currency Format Strings

    Country Currency Format
    Australia Dollar AU$#,0.00
    Canada Dollar C$#,0.00
    Denmark Krone kr#,0
    Euro Zone Euro € #,0.00
    Japan Yen ¥ #,0
    Sweden Krona kr#,0
    Switzerland Franc CHF#,0.00
    United Kingdom Pound £ #,0
    United States Dollar US$#,0.00
  3. Verify the table looks correct, and then click Load.

    Screenshot of Create table dialog.

  4. Repeat the previous steps for the following table:

    Table name: Yearly Average Exchange Rates

    Country Currency Year Yearly Average Exchange Rate
    Australia Dollar 2022 1.442
    Australia Dollar 2021 1.332
    Australia Dollar 2020 1.452
    Australia Dollar 2019 1.439
    Australia Dollar 2018 1.34
    Australia Dollar 2017 1.358
    Canada Dollar 2022 1.301
    Canada Dollar 2021 1.254
    Canada Dollar 2020 1.341
    Canada Dollar 2019 1.327
    Canada Dollar 2018 1.297
    Canada Dollar 2017 1.35
    Denmark Krone 2022 7.077
    Denmark Krone 2021 6.29
    Denmark Krone 2020 6.538
    Denmark Krone 2019 6.67
    Denmark Krone 2018 6.319
    Denmark Krone 2017 6.864
    Euro Zone Euro 2022 0.951
    Euro Zone Euro 2021 0.846
    Euro Zone Euro 2020 0.877
    Euro Zone Euro 2019 0.893
    Euro Zone Euro 2018 0.848
    Euro Zone Euro 2017 0.923
    Japan Yen 2022 131.454
    Japan Yen 2021 109.817
    Japan Yen 2020 106.725
    Japan Yen 2019 109.008
    Japan Yen 2018 110.424
    Japan Yen 2017 116.667
    Sweden Krona 2022 10.122
    Sweden Krona 2021 8.584
    Sweden Krona 2020 9.205
    Sweden Krona 2019 9.457
    Sweden Krona 2018 8.703
    Sweden Krona 2017 8.894
    Switzerland Franc 2022 0.955
    Switzerland Franc 2021 0.914
    Switzerland Franc 2020 0.939
    Switzerland Franc 2019 0.994
    Switzerland Franc 2018 0.979
    Switzerland Franc 2017 1.024
    United Kingdom Pound 2022 0.811
    United Kingdom Pound 2021 0.727
    United Kingdom Pound 2020 0.779
    United Kingdom Pound 2019 0.784
    United Kingdom Pound 2018 0.75
    United Kingdom Pound 2017 0.808

Create a Year column

A new Year column is needed in the existing Date table.

  1. In Model view, right-click the Date table, and then select New column.

  2. In the DAX formula bar, enter the following expression: Year = YEAR([Date]), and then press Enter.

    Screenshot of Year formula in DAX formula bar.

Create relationships

Relationships are needed between your new Yearly Average Exchange Rates and Country Currency Format Strings tables, and between Yearly Average Exchange Rates table and the existing Date table.

  1. If you have Autodetect for relationships on, the relationship between Country Currency Format Strings and Yearly Average Exchange Rates on the Country column may have been created for you. If not, then create this relationship:

    • Table 1: Yearly Average Exchange Rates
    • Table 1 Column: Country
    • Cardinality: Many to one
    • Table 2: Country Currency Format Strings
    • Table 2 Column: Country
    • Make this relationship active: Yes
    • Cross filter direction: Single

    The relationship should look like this:

    Screenshot of Relationship properties between Country Currency Format Strings and Yearly Average Exchange Rates.

  2. If you have Autodetect for relationships on, a relationship between Country Currency Format Strings and Sales territory on the Country column may have been created. This relationship, however, isn't correct for our model. In Model view, delete this relationship.

  3. Instead, create a relationship between Yearly Average Exchange Rates and Date on the Year column.

    • Table 1: Yearly Average Exchange Rates
    • Table 1 Column: Year
    • Cardinality: Many to Many
    • Table 2: Date
    • Table 2 Column: Year
    • Make this relationship active: Yes
    • Cross filter direction: Single (‘Yearly Average Exchange Rate’ filters ‘Date’)

    The relationship should look like this:

    Screenshot of Relationship.

  4. Save your model.

Create a measure group table

A measure group helps you organize different measures by having them in a single table.

  1. In the Home ribbon, select Enter data.

  2. In the Create Table dialog, leave the values blank. Name the table Sales measures, and then click Load. This table contains your new measures.

Create measures

  1. In the Data pane, expand and right-click Sales measures, and then select New measure. Enter the following DAX expression into the DAX formula bar, and then press Enter:

    Sales Amount = SUM(Sales[Sales Amount])
    

    It should look like this:

    Screenshot of Sales amount measure DAX formula.

  2. In Sales measures, right-click Column1, and then select Hide in report view. This changes Sales measures to a measure group, which now appears at the top of the Data pane with a measure group icon, like this:

    Screenshot of Column1 in Sales measure group.

  3. You can now create a measure to compute the exchange rate. Right-click Sales measures, select New measure, enter the following expression into the DAX formula bar, and then press Enter:

    Exchange Rate (Yearly Avg) = 
    IF (
        ISBLANK ( SELECTEDVALUE ( 'Country Currency Format Strings'[Country] ) )
            || SELECTEDVALUE ( 'Country Currency Format Strings'[Country] ) = "United States",
        1,
        AVERAGE ( 'Yearly Average Exchange Rates'[Yearly Average Exchange Rate] )
    )
    
    

    It should look like this: Screenshot of Exchange rate dax formula in DAX editor.

  4. Now you create another measure to convert the Sales Amount measure to other currencies. Right-click Sales measures, select New measure, enter the following expression into the DAX formula bar, and then press Enter:

        Converted Sales Amount = 
        SUMX('Date',
        CALCULATE( [Sales Amount] * [Exchange Rate (Yearly Avg)]))
    
    

    The Sales measures measure group should now look like this: Screenshot of Converted sales amount measure formula.

Create a report

  1. Go to Report view. Add a new, blank page to the report.

  2. Add a line chart visual to your new report page. You use this visual to see your measure before adding the dynamic format string for measures.

  3. In the Data pane > Sales measures, select Converted Sales Amount. Without clicking anywhere else, also select Year in the Date table.

    Screenshot of Line chart visual in Report view.

  4. Copy and then paste the visual so you have two line chart visuals. Change the second line chart visual to a table visual, and then move it below the line chart, like this:

    Screenshot of Copy line chart visual.

  5. Add a slicer visual to your report page. In the Format ribbon, add Country from the Country Currency Format Strings table to the slicer.

    Screenshot of Country slicer.

  6. Rearrange the visuals until they have a better layout, something like this:

    Screenshot of Rearrange visuals.

  7. While not required, you can change visual properties to make a nicer report:

    Slicer

    • Slicer settings: Single select
    • Size and Style, Padding: 10 px, all edges
    • Size and Style, Visual border: light grey, 10 px rounded corners
    • Slicer settings, Style: Tile
    • Slicer header: Off
    • Values, border: Left, #333333, 6 line width

    Table

    • Size and Style, Padding: 10 px, all edges
    • Size and Style, Visual border: light grey, 10 px rounded corners
    • Grid, Horizontal gridlines: White, 2 width
    • Grid, Vertical gridlines: White, 2 width
    • Grid, Border: White
    • Grid, Options: 2 row padding
    • Values, Values: Background color #F6F4F4
    • Values, Values: Alternate background color #F6F4F4
    • Column headers, Text: Bold, Text color white, Background color #0D6ABF

    Line chart

    • Size and Style, Padding: 10 px, all edges
    • Size and Style, Visual border: light grey, 10 px rounded corners
    • Title, Subtitle: On
    • Y-axis, Title: Off
    • Y-axis: Off
    • Markers: On
    • Data labels: On
    • Data labels, Values: Bold, Blue

    Canvas (optional)

    • Canvas background: light grey, 85% transparency

    With those visual properties, you get a nice report page, like this:

    Screenshot of Gray canvas background for visual.

Create a dynamic format string

Selecting different Country names in the slicer shows the Converted Sales Amount measure result in visuals, but not in the right format for that country or region.

  1. In the Data pane > Sales measures, select Converted Sales Amount.

  2. In the Measure tools ribbon, click the Format drop down, and then select Dynamic.

  3. The dropdown listbox to the left of the formula bar should now say Format, and the formula in the formula bar should have a format string. Replace the format string with the following DAX expression, and then press Enter:

    SELECTEDVALUE ( 'Country Currency Format Strings'[Format], "\$#,0.00;(\$#,0.00);\$#,0.00" )
    

    It should look like this:

    Screenshot of Country Currency Format Strings dynamic formula.

  4. Select a different Country in the slicer. The table and line chart visuals should now show the converted currency amount, in the correct format, for that country or region. Try selecting a different country/region in the slicer to see how the visuals change.

    Screenshot of Converted sales amount visual.

  5. Save your model.

Known issues and considerations

During Preview, the following issues and limitations are being addressed:

  • Visuals have formatting options that may impact how the format string is displayed. If the formatting is showing unexpectedly in a visual, go to the visual Format options, search for Display units and change it from Auto to None.

    Screenshot of Display units from auto to none.

  • The measure itself can be referenced directly in its dynamic format string by using its name, like [Measure A], or indirectly by using SELECTEDMEASURE().

  • Dynamic format strings for measures are only for model measures. Report measures that can be added to a live connect report can't have dynamic format strings for measures.

  • With DirectQuery for Analysis Services, when you click Make changes to this model on a live connect report, it shifts the connection to the DirectQuery over Analysis Services. In general, you can make changes to the format strings of the remote model measures. During Preview:

    • Remote model measures with dynamic format strings defined are blocked from making format string changes to a static format string or to a different dynamic format string DAX expression.
    • Remote model measures can't be changed from a static format string to a dynamic format string DAX expression defined in the local model.
    • Local model measures are blocked from using dynamic format strings for measures.