Year	Overall average
2004	67.7777777777778
2005	70
2006	70
2007	68.8888888888889
2008	68.8888888888889
2009	72.2222222222222
2010	72.2222222222222
2011	72.2222222222222
2012	77.7777777777778
2013	77.7777777777778
2014	74.4444444444444
2015	72.2222333333333
2016	71.1111
2017	68.8889
2018	74.4445