Year	number
2003	11.217391304347826
2004	11.133333333333333
2005	11.25
2006	10.90625
2007	10.78125
2008	10.40625
2009	10
2010	9.787878787878787
2011	9.151515151515152
2012	9.194444444444445
2013	8.931351351351353
2014	8.742162162162163
2015	8.591052631578949
2016	8.485789473684212
2017	8.248947368421053
2018	8.170000000000002
2019	7.973684210526316