HP Intelligent Management Center Standard Software Platform - Manual (Page 260)

Understanding running totals
Running total fields are similar to summary fields but allow more control over
how the total is calculated and when it is reset. Running total fields are
specifically suited to perform the following totaling functions:
• Show values of a total accumulate as it is calculated record by record.
• Total a value independent of the report's grouping.
• Total a value conditionally.
• Total a value after a group selection formula has been applied.
• Total a value from the driving table in a one-to-many linking relationship.
How running totals work
A running total field is created with the Running Total Expert. The Running
Total Expert creates a running total field by asking you to select a field to
summarize, the summary operation to use, a condition upon which to base
the evaluation, and a condition upon which to reset the evaluation.
Note:
A running total field can be used on database fields and first-pass formulas,
but cannot be used on second-pass formulas or formulas that reference
other second-pass formulas. For more information see "Multi-pass reporting
flow chart".
Placement of running total fields
The calculation of a Running Total field is determined by the settings selected
in the Running Total Expert. However, where you place the running total
affects the value that appears on the report. For example, if a Running Total
field that evaluates every record and never resets (a grand total) in the Report
Header, only the value of the first record will appear. Placing the same
Running Total field in the Report Footer returns the desired value. The
Running Total field is properly calculated in both cases, but it is displayed
too soon in the first case.
260 Crystal Reports 2008 SP3 User's Guide
Running Totals 11
Understanding running totals