The Derive function is necessary to create or derive a data field previously loaded. This function will use the table created using the Declared syntax. In my example code, I derive all fields that have been tagged with $myAmount.

To test and see the actual output generated by the Declare and Derive syntax, you can perform the following steps:

1. Run the script with the code shown in this section by clicking the Load Data button and then save it.
2. Using the navigation menu, click on App Overview. 
3. Click on Create New Sheet.
4. Click on Edit to edit the sheet.
5. From the left pane, click on the first icon, Charts. 
6. Locate the chart Table. Drag and drop Table onto the sheet.
7. Click on the Dimension button and add the Amount field (coming from the source) and also add the AmountInThousands, AmountInMillions, and AmountGroup fields, which are the derived fields. The following screenshot shows what the output will look like: