Using Actuate BIRT Viewers : Functions and operators : ADD_MINUTE( )
 
ADD_MINUTE( )
Adds a specified number of minutes to a date value.
Syntax
ADD_MINUTE(date, minutesToAdd)
Arguments
date
The date or date expression representing the start date. If a start date does not have a time value, the function assumes the time is midnight, 12:00 AM.
minutesToAdd
The number of minutes to add to the start date. If you specify a negative number, the result is as if the number is subtracted from the start date.
Returns
The date‑and‑time value that results from adding the specified number of minutes to the start date.
Example
The following example subtracts 30 minutes from each date in the StartTime data field:
ADD_MINUTE([StartTime], ‑30)