Say I put into pivot a number of bananas eaten by the monkey, sliced by months and days. How to add a column containing average number of bananas eaten by the monkey over all period of time?
Sure I can get it by collapsing all months and days - but that's not a solution for me as I need to include into pivot some more values with formula based on this average and individual value.

Average per day? Average per month? Both? Can you just do a calculation separate from the pivot table?

Per all period of time currently displayed in pivot table.
No, I want to include it into pivot table.