When you enter a mathematical calculation in the Related Formulas/Rows/Units cell, also enter either the letter of a column in the report (for example, A.120 to denote column A, row code 120), or use the at sign (@) to indicate all columns (for example, @120 to denote all columns in row 120).
Any number that does not have a column letter or an at sign (@) is assumed to be a real number.
If you reference a row by using a label row code, you must separate the column letter from the label with a period (.). For example: A.GROSS_MARGIN/A.SALES
The at sign (@) does not require the period separator. For example: @GROSS_MARGIN/@SALES