Last 12 month's average

Originally Posted by Kevin UK

Hi simonlblea

Try the Index & Match (Non volatile)

Formula:

=AVERAGE($A3:INDEX(3:3,MATCH("Rolling average",$1:$1,0)-1))

Or

Formula:

=AVERAGEIF($A3:INDEX(3:3,MATCH("Rolling average",$1:$1,0)-1),">0")

If you need to exclude zero values when averaging.

Wouldn't this always include A3, so it becomes 13 cells when inserting 1 column.
Then 14 after another column is inserted, then 15 etc..