Year	Number of
1990	211.27
1991	216.97
1992	220.24
1993	225.02
1994	231.56
1995	233.65
1996	236.98
1997	249.26
1998	256.84
1999	256.02
2000	261.9
2001	264.73
2002	270.42
2003	279.03
2004	276.35
2005	284.39
2006	286.7
2007	301.44
2008	310.25
2009	317.68
2010	327.58
2011	340.68
2012	353.72
2013	366.68
2014	379.31
2015	389.75
2016	402.02