Year	Number
1999	9.45098
2000	9.62195
2001	9.57647
2002	10.01258
2003	9.89349
2004	9.7931
2005	9.23684
2006	8.94872
2007	10.05405
2008	10.52582
2009	9.50649
2010	10.40179
2011	10.98246
2012	9.89057
2013	10.35965
2014	10.64655
2015	13.55814
2016	8.56835
