What are category columns? 

1. Number category columns - To group numerical data into columns
   
2. Picklist category columns - To group picklist data into columns

Notes :

You can only add category columns for numeric and picklist values. It is not supported for any other values.

The numeric field types supported are Number, Long Integer, Currency, Percent, Decimal.

You can only create a maximum of two category columns in a report. 

Number category columns    

Scenario 

1. Go to the Reports tab and select the report for which you want to add category columns.
   
2. Edit the available columns by clicking the Edit icon on the right. Click the + icon near the Column header to add category columns.
   
   
3. Select the new category column source from one of the numeric fields available. The numeric fields supported are number, long Integer, currency, percent, decimal, formula, and roll up summary. The source column is 'Weight' in this example.
   
4. Enter the new category column name. Click Create Category. As per the scenario stated above, the category name we've entered is Weight Category.
   
   
5. Enter Categories and define start and end range values for each.
   
6. Enter the category names and input the start and end range values in a continuous order. To add a new category, click the green + icon.
   Note : We've ensured that range values are continuous to prevent any report value from falling into the uncategorized section unintentionally.
   
7. Add the lowest range or highest range for values from Settings. The ranges for these categories will be automatically set based on your range inputs. In the example, We have three ranges:
   -- Underweight: Below 14 kgs [ Low Range ]
   -- Normal: Between 14 to 17 kgs [ Middle Range ]
   -- Overweight: Above 17 kgs [ High Range ]
   
8. Add a default category : (see screenshot above)
   Any uncategorized value not falling in the above ranges will fall into the default category, which is defined as 'New Born' for this example.
9. Add empty category : (see screenshot above)
   You can choose to show empty values as a separate category and name the column to easily understand why those column values are empty. It will be 'Undefined' for this example.
10. Click Done to save the changes made to the report.
    
11. Once saved, the column values will be checked against the specified criteria, and the record will be marked with appropriate categories automatically, as shown in the screenshot.
    
    

Notes :

1. We can select the category columns for row or column groups as well.
2. The numeric field types supported are Number, Long Integer, Currency, Percent, Decimal.
   
3. You can add up to 10 categories apart from the two system defined minimum and maximum categories.
   
4. You can also add the category columns to row groups and column groups. A maximum of two categories can be added to the row and column groups.

Picklist category columns    

Scenario

1. Go to the Reports tab and select the report for which you want to add category columns.
   
2. Edit the available columns by clicking the Edit icon on the right. Click the + icon to add category columns.
   
   
3. Select the source column from one of the picklist fields available, which is 'Country' in this example.
   
4. Enter the new category column name. Click Create Category. We've entered Customer Region as the category column name for this example.
   
5. Enter the category name and select the values that must be categorized into it and click Done. For the example, we've entered the category name as 'North' and selected the countries that fall in the north region.  
   
6. Click New Category to add more categories.
   
7. Enter the category names and select values for each and click Done. For the example, we've entered three more categories South, East, and West, and selected the countries that fall in those respective regions.
   
8. Add a default category : (see screenshot above)
   Any uncategorized picklist value will fall into the default category. In this example, all uncategorized values will be marked as 'New Country'.
9. Add empty category : (see screenshot above)
   You can choose to show empty values as a separate category and name the column to easily understand why those column values are empty. In this example, all empty records will be marked 'Undefined'.
10. You can reorder categories to reflect their priority while being sorted. Simply drag and drop the category name to its desired location, as shown in the screenshot below.
    
11. Click Run and then Save to activate the report.
    
12. The column values will be checked against the specified criteria and placed in their proper categories automatically, as shown in the screenshot.
    
    
    

Notes :

1. You can add up to 10 categories and up to 20 values for each category.
   
2. You can also add the category columns to row groups and column groups. A maximum of two categories that can be added to the row and column groups.