Formula for common end date
I'm trying to figure out how to have several tasks point to a common end date. The tasks have various implementation dates but the "go live" time period ends at the same time (i.e., 2 tasks - one completes on 6/13 and the other completes on 7/1 but the project end date is 12/31 for both...so different durations and I don't want to have to change multiple rows, just one). How can I point to the row that contains the project end date? The formula I'm trying isn't working which is basically "=[End Date]5" since row 5 has the date I want.