Year	Number of
1990	405.01
1991	415.77
1992	429.17
1993	446.66
1994	469.41
1995	494.89
1996	509.16
1997	515.39
1998	528.02
1999	529.81
2000	537.49
2001	533.23
2002	533.13
2003	534.88
2004	535.11
2005	525.38
2006	512.33
2007	502.82
2008	489.19
2009	482.21
2010	475.88
2011	464.98
2012	453.69
2013	440.12
2014	431.49
2015	423.03
2016	416.46