Is it possible to keep track of the original due date for tasks and milestones if you change the due date?

Is it possible to keep track of the original due date for tasks and milestones if you change the due date?

One common aspect of project management is to be able to analyze the difference between what I originally budgeted for in terms of total time for a project vs how much time did I actually use in the end.  Is there a way to do this in ZoHo Projects?