Basically, I have a spreadsheet where I add in a new column of numbers every day. I have been keeping track of the average for each row, but now am looking to keep track of the average for only the most recent 10 columns.

Is there a way for a formula to start with the right-most column (which changes every day) and then look back from there to find the average for the 10 most recent columns without me having to manually change the range every day? Does that even make sense to anyone except me?