Question How to Calculate values form subform

[good2zain]

Main form

Attendence Sheet

Registration no 1318-FAS Primerykey
student name Ali
father name Ahmed

Sub form
composite key :Registration no, Month

Registration no Month Lecture_dilivered absents Total_attended(%)
1318-FAS....... Sep....... 10................. 2............. 80
1318-FAS....... Oct........12.................. 0............ 100
1318-FAS........Nov.......10.................. 2............. 80


Final Percentage= sum of all rows in Total_attended(%) column / no of rows


subform is in data sheet view , how to calculate the final percentage ?

 

[neileg]

I would do the calculation in the footer of the subform and then reference the control on your main form. You can't see the footer in datasheet view, so switch to continuous forms, add the control and switch back.

Now the real problem you have is that averaging percentages like this is not mathematically meaningful. If you average your percentages you get 87%, if you calculate on the base data you get 87.5%