My report is calculating the attendance of the company employees, sometimes, one of the staff forgot his id card and in that case he will not punch and the system will not record his attendance time and it will display nothing in the field as shown below, this is causing me a problem with calculating the total, so I was trying to make the report check when ever this value is null must display 0 instead in this field
Shift Starts Entry Mins Late Shift Ends Exit Mins Early
08:00am 08:30am 00:30 03:00pm 02:50 00:10
08:00am 09:09am 69:00 03:00pm 02:55 00:05
08:00am 03:00pm 07:30 00:00
Total: 77:30 Total:00:15
but in other records which doesn't have empty field, the total has been calculated correctly