Year	Number
1994	14.64158
1995	14.22229
1996	13.29838
1997	12.9214
1998	13.07663
1999	13.20143
2000	13.25397
2001	13.44778
2002	13.60084
2003	14.18637
2004	14.44809
2005	14.03529
2006	13.46965
2007	12.77224
2008	12.27448
2009	11.71826
2010	12.0762
2011	12.34899
2012	12.30516
2013	12.37946
2014	12.46555
2015	12.49049
2016	12.25572
2017	12.59088
2018	12.62595