we need to create a calculated field that displays the count of returns only for the first year in the table. To do this, we can use the following formula:

IF FIRST () = 0 THEN COUNT (Returns) END

This formula uses the FIRST () function, which returns the number of rows from the current row to the first row in the partition. If the current row is the first row, then FIRST () returns 0. The IF statement checks if this condition is true, and if so, it returns the count of returns for that row. Otherwise, it returns NULL.

To complete the formula in the calculated field, you should select the following options from the drop-down menus:

FIRST ()

0

COUNT (Returns)

https://help.tableau.com/current/pro/desktop/en-us/functions_functions_date.htm