Calculating a time based on a text feild controlled by a combo box?

[Etoimos]

I have a form that contains a set of combo boxes that allows the user to select an Event (ICREventCombo) and then a set of senarios (ICRScenarioCombo) from that event. ICRScenarioCombo has the following Row Source:

SELECT Scenarios_tlb.Test_Case_Number, Scenarios_tlb.Event_Name, Scenarios_tlb.Sim_Time_Data, Scenarios_tlb.Sim_Time FROM Scenarios_tlb WHERE (((Scenarios_tlb.Event_Name)=[Forms]![BOA ICR Times]![ICREventCombo])) ORDER BY Scenarios_tlb.Test_Case_Number; 

It is formated as a General Date.

I also have a text box (Sim_Time_Data) with the following Control Source:

=[ICRScenarioCombo].[column](2)

I would like to create a second text box that subtracts 3 minutes from the

Sim_Time_Data text box. How can I do that?

[ranman256]

=dateadd("n",-3,Sim_Time_Data)

[Etoimos]

=dateadd("n",-3,Sim_Time_Data)

I just got back from vacation to see your reply and it worked perfectly. Thank you.