Year	Number of
1990	433.71
1991	443.78
1992	440.73
1993	442.59
1994	445.94
1995	455.08
1996	438.17
1997	424.59
1998	410.84
1999	412.24
2000	416.45
2001	416.36
2002	417.99
2003	424.3
2004	456.53
2005	493.35
2006	523.27
2007	522.8
2008	529.17
2009	537.7
2010	546.47
2011	552.17
2012	558.54
2013	564.4
2014	569.96
2015	585.43
2016	602.26