Hi Daniel, Your calendar names are easy to incorporate into Duration1=IIf(InStr(1,[Task Calendar],”2s”),[Duration]/(20*60/[Minutes Per Day]),[Duration]).
Re. resource calendars, you can’t reference them directly in a task custom field formula. (If its important for such things, then you either need to add an intelligent calendar-name extension to each resource name as I showed earlier, or do the whole thing with vba.) Good luck, tom