Hi Brian,
I don't have a good way to do this with standard ledger. The ledger
--average option is a little opaque; at least, it does not behave the
way I would expect. Maybe there's a straightforward way to do this with
the balance report using a format string (e.g., divide the total for
each account by the number of periods)? I hope someone else can give a
better answer to this question!
But I wanted to say that one reason I have both ledger and hledger
installed is that hledger handles this kind of thing very nicely. In
hledger,
hledger -f all.ledger bal Expense -p monthly --average
does exactly what you want, I think. In general, I find the behavior of
--average in hledger a lot more intuitive.
HTH,
Richard