Fred,
Depending on what type of data you want to see there are different ways
to do it. For a simple 3 month filter I always use the 90 day approach.
It is not exactly 3 months but generally close enough. Just set up the
filter for "Today + 90ed". It's been a while since I did it but I think
I used an interactive filter to achieve the "Today + 90ed" date. You
could also put the value in a custom field so it is automatically
calculated and then query that field in the filter.
Another approach you might want to consider is to use one of the Usage
views with a timescale set for "quarters". Try either Task Usage or
Resource Usage and see which provided the data you need. With these
views you probably won't need any filtering.
John
