Thx for your kindly reply.
But i don't have self-referencing table. I would like to tell my
calculation's details and post some code. But i am not familiar with
accounting terms in English and codes are too complex to understand
with one look in this context.

What i can say about is, i discovered that recursive calls can be
useful when extracting a retroactive list of account states from records.

I am trying to make the technique optimized.

My last decision is doing temporary work around about this issue and
waiting for stable version of FB 2.1 for Global Temporary tables.
Maybe FB should have Global Named Cursors :)