HOw to calculate 12 Months rolling Average

Hi,

I am working on a webi which should have a calculated column as Rolling Average for last 12 months.

For one day I get 24 records. So for those months which has 30 days I get 720 and with 31 days i get  744.

I researched and referred following threads but nothing worked. Values are still not correct.

Calculating Moving Averages in Web Intelligence | Business Intelligence Articles from www.gulland.com

how to calculate 16 days moving average in WEBI

How to Create a Moving Average in Webi Report

BOBJ Tricks: Moving Average in Webi

Anyone please help.

Regards