I'm designing a form on which there will be elapsed time for an activity. I want to have two unbound list box controls, one for hours and another for minutes. In this particular application minutes will be reported only in 15 minute intervals. The hour list box will have 1, 2, 3, 4. The minute list box will have 00, 15, 30, 45. I'd like to have a third not visible control that is bound to a field in the table with regular date/time format. The conversion from the list boxes to the bound control will take place in the list boxes AfterUpdate events. What formula do I use for the conversion?