Rolling 12 Month Average - Sample Data Inside

[nguyeda]

Help! I swear I figured this out earlier today and I was like "that's easy enough to remember" then I couldn't do it again

Here is what I need help with:

Say for Material A: I need Access to see that the 1st date is 05/01/2013 and say 365 days out or 12 months (05/01/2013-04/01/2014) the average is 158.6 then 06/2013-05/2014 the average is 146.667 and so on.

Every month is not going to be listed in the results, if there is no month then assume 0.

Sample data attached.

:banghead:

 

[nguyeda]

I have a lot of scenerios where I need to do rolling formulas, so it'd help if I could learn some lessons here