Year	1=extremely inefficient to 7=extremely efficient
2007	4.32307692307692
2008	4.39628634445201
2009	4.785481533
2010	4.9567484
2011	4.9
2012	4.9
2013	4.8
2014	4.7
2015	4.50811008271717
2016	4.5
2017	4.9