Unable to apply graduated symbols to certain fields

Description

In ArcGIS Pro, certain fields are not listed for the Field parameter when applying graduated symbols.

In some instances, the following warning message is returned when the Graduated Colors option is selected:

Warning:   
Layer does not contain any field types that can be used to quantify using graduated colors.

Cause

Graduated symbols are used to represent quantitative differences in map features. Therefore, applying graduated symbols to a text field instead of a numeric field is not possible.

Solution or Workaround

As a workaround, create a new numeric field and populate the field with data from the text field. Follow the steps below to do so.

1. Open the ArcGIS Pro project.
2. Open the layer fields view. Refer to ArcGIS Pro: Fields view for instructions.
3. In the fields view, add a new field with a numeric data type, such as short integer, long integer, float, or double.
   1. In the last row, click Click here to add a new field.
   2. Specify the Field Name and Alias of the new field. 'CRMID_NEW' is used in this example.
   3. For Data Type, select a numeric data type from the drop-down list. In this example, Long is selected.
   4. On the Fields tab, in the Changes group, click Save to save the edits.

4. Populate the new field using the Calculate Field tool.
   1. In the Geoprocessing pane, search for and select Calculate Field (Data Management Tools).
   2. In the Calculate Field pane, for Input Table, select the layer containing the text field from the drop-down list. In this example, 'SanFrancisco_customers' is selected.
   3. For Field Name (Existing or New), select the field created in Step 3. In this example, 'CRMID_NEW' is selected.
   4. For Expression, double-click the field with the values to be copied to the new field. The 'CRMID' field is used in this example.
   5. Click Run.

The attribute table displays the 'CRMID_NEW' field populated with the values from the 'CRMID' field.

5. Apply graduated symbols to the field.

The 'CRMID_NEW' numeric field is listed for the Field parameter and graduated symbols are applied to the field.