Physical verification of all contingent owned stores, equipment and vehicles and UN owned accountable items when a member nation's contingent enters the mission area; the actual amount of the reimbursement for COE is based on the marching-in survey (which is thereafter constantly updated as issues and receipts are posted and as write-offs occur), and, in the case of equipment/stores deployed for less than four years, a 'marching-out survey' is done when it leaves the mission area; these surveys are carried out by the contingent as well as by UN experts who assess the actual value of the equipment as it enters and leaves the mission area and are used by the UN as a basis for settlement of government claims for reimbursement.