Year	Number of
1990	441.13
1991	448.81
1992	458.36
1993	469.5
1994	482.37
1995	496.79
1996	501.48
1997	507.71
1998	514.71
1999	522.03
2000	530.21
2001	532.68
2002	536.1
2003	539.14
2004	542.48
2005	546.46
2006	555.13
2007	565.17
2008	575.8
2009	586.29
2010	597.11
2011	600.73
2012	605.2
2013	609.3
2014	613.39
2015	618.39
2016	623.91