## 4 Conclusions  
The main objective of this project is the development of a new KPI that measures the six big losses in an economic dimension and can be implemented in a CPS to its real-time calculation. Moreover, it completes our previous research about six big losses in productive and sustainable dimensions.  
Our research supports the idea that Industry 4.0 enhances the machining tool analysis and decision-making for companies. CPS is able to acquire real-time data, process them to obtain real-time indicators for machine tool monitorization and display several visual information through different diagrams and indicators which inform companies at a glance about the machine health. Moreover, the continuous monitorization has a predictive maintenance component, an abrupt and anormal value of one of these KPIs can be interpreted as a machine tool failure, thus, notice should be given for review.  
The new KPI development and its comparison with the OEE, OEE', and ECL, whose origin is the same: the six big losses; it provides companies with a competitive advantage. Not only does it allow companies to compare the losses in three different areas: production, sustainability, and economy, but it also allows the development of a multidisciplinary decision-making tool. This multidisciplinary analysis is considered more reliable than single factor analysis, thus, production decisions should involve several parameters and variables [39].  
This research has improved our knowledge about aspects such as the process of CPS implementation and its features, specially KPI implementation. With the acquired knowledge, we can extrapolate this to other SC processes and systems, which is one of the limitations of this research, given that this KPI implementation has been made for a single machine. For further research, the horizontally or vertically integration of these KPIs--towards other processes in the SC or towards other logistics operations-would be considered. The majority of the companies, which are using Industry 4.0 technologies or are nearly to use them can implement this technology in several resources, i.e., machining tools, 3D printers, Automated Guide Vehicles (AGVs), manufacturing systems, or forklifts. Furthermore, we have implemented a CPS in another machine-tool in order to create a machine park, expand the KPI development and analyze the communication machine to machine.  
Figure 11: Comparison between OEE’, ECL, and new KPI.  
To conclude, the outcome of our research highlights the importance of attending to different dimensions (productive, sustainable, and economic) towards with the importance of implementing industry 4.0 technologies in companies to acquire a competitive advantage over the competition.  
Conceptualization, P.M. and M.P.L.; Investigation, P.M. and M.P.L.; Methodology, P.M. and M.P.L.; Project administration, J.R. and J.C.S.; Resources, J.L.; Software, P.M.; Supervision, M.P.L. and J.R.; Validation, M.P.L.; Writing--original draft, P.M.; Writing--review & editing, M.P.L. All authors have read and agreed to the published version of the manuscript.  
This research received no external funding.  
The authors would like to acknowledge the participation of the Precision Mechanic Service of the Universidad de Zaragoza during the essays, as well as, the collaboration of TECNALIA RESEARCH & INNOVATIONS in the implementation of the CPS and for their expertise in electronics and communication.  
The authors declare no conflict of interest.