Calculate Accounting period based on 12 date ranges

Good afternoon/morning depending where you are

Any advice on this very welcome

I Need a formula that converts a date column to a specific outcome in Excel 2007. I tried if and but run out of nested arguments

Date column `M` is standard date format.

Then a period column `AO` looks at the date cell and then needs to return the following outcome when M is updated

'AP01' if dated 1/1/12 – 4/2/12
'AP02' if dated 5/2/12 – 3/3/12
'AP03' if dated 4/3/12 – 6/4/12
'AP04' if dated 7/4/12 – 4/5/12

and so on for 12 periods

Is this possible either in a simple formula or through VBA if someone could point me in that direction

Many thanks

Nikk

Thx Pepe

So would I need to put the date ranges in a sep sheet and make reference to the mini table.

I am assuming this to be the case as the table where I want the calculation to occur is effectively and Excel based linear database

Appreciate your support