Yes, and ocean carriers' managerial accounting systems may actually assign credit to shipments that help reposition containers from surplus ports to shortage po

Yes, and ocean carriers' managerial accounting systems may actually assign credit to shipments that help reposition containers from surplus ports to shortage ports. So the actual cost of moving a container from Rotterdam to Shanghai might be $1,000 and the customer is only paying $500 but the office that sold the business can at least "break even" because they may also get a $500 credit for getting an empty box back to Shanghai where there's always a shortage, because of the opportunity cost of not having equipment available for the customer shipping from Shanghai to Rotterdam who will pay $3,000.