Calculated Fields

[liam_conor]

I have three fields on a subform: "Start Time" "End Time" "Minutes Lost". What I am trying to do is subtract "Start Time" from "End Time" and return the value of total minutes lost to the field "Minutes Lost". Here is the problem: I can subtract "Start Time" from "End Time" but I cannot get a number. Example: 12:00 - 15:00 = 3:00 instead of the number I want 180. The second thing is I cannot get the textbox "Minutes Lost" on the subform that is carrying out the calculation to store that value in the table field "Minutes Lost". This could be due to the fact that I am carrying out the calculation in the Control Source for the textbox on the subform. Any ideas or suggestions...

PLEASE HELP

 

[SydneyGeek]

Hi Liam,

try MinutesLost: ([EndTime]-[StartTime])*24*60. A question: do you really need to store the Minutes Lost? If it's a calculation (which it is), you're best off leaving it as a query field and using the query for reporting. Otherwise, subsequent changes to the Start or End time will result in errors in your data.

Denis

 

[Norie]

Why not use the DateDiff function?

eg DateDiff("n", [EndTime]-[StartTime])