Need help in calling row values in pivot formulas

[zima8172]

I would really appreciate your help in fuguring this one out. I built a pivot to automate the generation of cashflow statements. I have month as pivot's columnar dimensions -- 1,2,3 etc and $$$ as values. I'd like to add a formula to calculate closing and opening values, for example, closing value for month 1 is the opening value of month 2.

Thanks a lot!