Year	Number of
1990	423.5
1991	440.03
1992	460.55
1993	480.82
1994	504.72
1995	531.88
1996	558.18
1997	587.61
1998	621
1999	650.94
2000	681.46
2001	713.42
2002	743.75
2003	775.45
2004	812.76
2005	849
2006	882.64
2007	920.45
2008	955.47
2009	988.19
2010	1024.3
2011	1063.68
2012	1100.99
2013	1134.05
2014	1172.34
2015	1211.06
2016	1249.5