How to summarize a formula field in crystal reports?

Question

How do I add a running total or summary field on a formula field in crystal reports?

// Sample Report

 Serial No.       Premium        Commission         Net (Premium-Commission)
-----------------------------------------------------------------------------
    1.              10               4                    6        
    2.              40              30                   10
  ---------------------------------------------------------------------------
  Grand Total       50              34                   16

In sample report, Net (Premium-Commission) is a formula field which gets evaluated for each row? How do I add a grand total/summary field for my formula? It seems we can add a summary field to only Command fields.

Answer 1

Suppose Net (Premium-Commission) formula field name is {@Net}. Now you have to create another three formula fields.

1. Initializer: this formula filed will be placed in header section to reset all variables.
2. Increment: this formula field will be placed in detail section to summarize the value.
3. Total: this formula field will be placed in footer section to show total of {@Net}.

Code will be writen in formula fields as below.

{@Initializer} WhilePrintingRecords; Numbervar dSum :=0;

{@Increment} WhilePrintingRecords; Numbervar dSum; //Don't initialize zero dSum:=dSum+{@Net}; //{@Net} formula field must be return numeric value

{@Total} WhilePrintingRecords; Numbervar dSum; //Don't initialize zero dSum;

Place all formula fields in their appropriate section and suppress {@Initializer} and {@Increment} formula field.