The following instructions can be reviewed in the attached workbook, which can be found in the upper right-hand corner of the webpage.

Option 1 - Create a calculated field

1. Click the down arrow next to Dimensions in the data pane and select Create Parameter…
2. In the Create Parameter dialog, do the following and click OK:
   1. Name the parameter. In this example, the parameter is named "Sales Threshold"
   2. For Data Type, choose Float
3. Right-click [Sales Threshold] in the data pane and select Show Parameter Control
4. Select Analysis > Create Calculated Field
5. In the Calculated Field dialog box that opens, do the following, and then click OK:
   1. Name the calculated field. In this example, the calculated field is named "Customer or Others"
   2. In the formula field, create a calculation similar to the following:

      IF { Fixed [Customer Name] : SUM(Sales) } >= [Sales Threshold] 
      THEN [Customer Name] 
      ELSE "Others"
      END

6. Drag [Customer or Others] to the Rows shelf
7. Drag SUM(Sales) to Details

Option 2: Use Set Actions

This example will create a bar graph showing the total sales of user-selected customers vs others. This uses the new Set Actions feature added in Tableau Desktop 2018.3

Step 1 - Create a Source sheet

This will be the sheet where the users will select customers from

1. Drag [Customer Name] to the Rows shelf
2. Drag [Sales] to the Columns shelf
3. Drag a second copy of [Sales] to Label on the Marks card

Step 2 - Create the Target Sheet

1. Right-click [Customer Name] in the data pane and select Create > Set…
2.  In the Create Set dialog, do the following and click OK:
   1. Give the set a name. In this example, the set is named "Selected Customers"
   2. Make sure there is at least one checked and one unchecked customer
3. Drag [Selected Customers] to the Rows shelf.
4. Right-click the word "In" in the view and select Edit Alias.
5. In the Edit Alias dialog, type something like "Selected Customers" and click OK.
6. Repeat steps 4&5 for "Out" and rename it "Other customers".
7. Drag [Sales] to the Columns shelf
8. Drag a second copy of [Sales] to Label on the Marks card.

Step 3 - Create the Dashboard

1. Create a new dashboard and add the source and target worksheets
2. Navigate to Dashboard > Actions…
3. In the Actions dialog, click Add Action > Change Set Values…
4. In the Add Set Action dialog, do the following:
   1. For Source Sheets, check only Source Sheet
   2. For Run action on, choose Select
   3. For Target Set, in the first drop-down select the data source being used
   4. For Target Set, in the second drop-down select Selected Customers
   5. For Clearing the selection will, select Remove all values from set
5. Click OK twice to close all dialogs.