Year	Overall average
2004	70.3030303030303
2005	72.3232324242424
2006	69.2592594444445
2007	69.6296294444444
2008	70.0925925
2009	69.3518522222222
2010	69.3518519444444
2011	69.1666666666667
2012	67.4074072222222
2013	68.8888888888889
2014	71.3888888888889
2015	72.0370388888889
2016	73.3333305555555
2017	73.7036972222222
2018	77.4999972222222