Year	years
2003	3.3466666666666667
2004	3.2625
2005	3.288888888888889
2006	3.2736842105263158
2007	3.210000000000001
2008	3.210000000000001
2009	3.21
2010	3.210000000000001
2011	3.1950000000000007
2012	3.1950000000000003
2013	3.13
2014	3.13
2015	3.13
2016	3.13
2017	3.13
2018	3.13
2019	3.13