We would like to know the calculation procedure for credit exposure, we are applying the credit chec

We have some customers for whom sales orders are already created in the application. We want to apply credit check to these customers. when we apply the credit check, we get a certain credit exposure in the credit exposure report. How does the system calculate that number to be the exposure of the customer. Also, with slight changes on the options in the credit check rules on the exposure tab, the exposure figure changes all the time. Which will be the correct options for us and which figure should be considered as our exposure?