[dedestan]

I'm wondering if it's possible to create dates for milestones as formulas.

We have quarterly production cycles where certain milestones are always a certain number of days from major milestones, but don't actually have durations that we track, and I'd prefer to see them as milestones and not task bars on the gantt.

For example, a major milestone might be the date the PO is placed at the factory (D[Day]). Two weeks prior to that we place orders from secondary suppliers (D-2W). One week after that we place an order for printed materials (D+1W). Sixteen weeks after the order is placed, the order ships (D+16W).

As these are set formulas for each quarterly production run, I'd like to set these as a template, and then each time I'd be able to put in a date for D, and everything would autofill based on the pre-set formulas.

Any ideas?

Thanks.

[Tom Bunch]

Sounds like you're looking for lead times. In a forward scheduled project, a lead time on a dependency would mean that the dependent task cannot start until at least X duration before or after the prerequisite is met. In other words, the dependency with lead time can cause a task to fall later than it would due to other factors, but cannot force it to fall sooner.

Consider the example file I'm including here, looking in particular at task 1) Order from secondary suppliers. Because task 2) Place PO is pushed out to 11/3/11, which is at least 2 weeks after the project start date of 10/18/11, task 1 does indeed fall 2 weeks prior to task 2. However if you change the project start date to 10/31, task 2 will not move and the lead time will be less than two weeks.

I've structured it that way because you stated that you want to set the date of the major milestone, "Place PO" and let the other dates be calculated from that. An alternative might be to make the major milestone dependent on ordering from secondary suppliers instead, and let pushing that order push all the related milestones along.

Play with it a bit and see if that fits your needs. You can always save a series of tasks like this in a template document and copy them into your working documents as you need them.

-Tom