When you modify a number or calculation in one column of a particular row but do not want to affect other columns in the report, you can specify CAL(for Calculation) in the Format Codecolumn of the row definition.
Modify a number in selected columns

To perform a calculation on all report ( FD) columns, do notenter a column assignment.

To restrict a formula to certain columns, enter the column letter followed by an equal sign ( =) and the formula.

You can specify multiple columns. When you use the at sign ( @) with specific column placement, the @relates to the row.

You can enter multiple column formulas in one row if they are separated by commas.
Example
This calculation 
Creates this action 

@130*.75 
The value in row 130 is multiplied for each column by .75, and then the result is put in the current row of every column. 
B=@130*.75 
The calculation is performed only on column B. 
A,B,C=(@100/@130)*.75 
A=(A.100/A.130)*.75B=(B.100/B.130)*.75C=(C.100/C.130)*.75 