1 Total revenue of all National Football League teams from 2001 to 2015 (in billion U.S. dollars)*Total revenue of the National Football League 2001-2015. 2  National Football League average franchise value from 2000 to 2016 (in million U.S. dollars)National Football League - average franchise value 2000-2016.
There are two types of systems in organizations: closed systems and open systems. An open system interacts with its environment through giving and receiving information. Closed systems are closed off from the outside environment, and all interaction and knowledge is transmitted within the closed system only.
In this paper, we highlighted the importance of integrating environmental goals into the production system. We recommend the establishment of closed-loop production systems in a supply chain level. To realize closed-loop production systems, we introduced the concept of sustainable supply chain networks. With a SSCN, it is possible to shift successfully from a flow economy to a circular economy by combining environmental and economic issues, thereby improving eco-efficiency.