What is field 1? What is field 2?
field1 is quantity and field2 is price
edit: field1, field2 and BalanceAmount all are number fields
3. needs to be an unstored calculation field--also cannot be a number field with auto-entered calculation or the value computed will not update to use the current date as time passes.
I would not define 1. as a calculation field. I'd put the rate in either a global field or a field in a related table so that I can change the interest rate withoug needing to redifine a field's calculation.
"Period" field is unstored calculation field as i need it to recalculate whenever it needs.
InterestRate field: you are right and i will change it.
thanks very much.