Hi Dev,
I have gone through your suggestion link. It is irrelevant to Customer interest calculation cost center derivation.
As per that link what ever suggestion same thing already done but i can not assign default cost center in KA02 because cost element is one but cost centers are may it has to go based on profit center, Cost element create, Field status optional for GL account and OKB9 done with combination of company code, cost element and account assignment details(profit center).
Thanks for suggestion. Still problem not resolved.
Regards,
Babu.