Year	years
2003	2.815384615384615
2004	2.815384615384615
2005	2.7785714285714285
2006	2.7785714285714285
2007	2.7624999999999997
2008	2.7624999999999997
2009	2.7624999999999997
2010	2.86875
2011	2.776470588235294
2012	2.7470588235294113
2013	2.717647058823529
2014	2.717647058823529
2015	2.717647058823529
2016	2.717647058823529
2017	2.717647058823529
2018	2.717647058823529
2019	2.6705882352941175