N.D. Cent. Code § 65-04-16: Adjustment of premium paid on estimated payroll

In the event that the amount of premium collected from any employer at the beginning of any premium period is ascertained and calculated by using as a basis the estimated expenditures for wages for the period of time covered by such premium payments, an adjustment of the amount of such premiums shall be made at the end of said period, and the actual amount of such premium shall be determined from the actual expenditure of wages for said period.