Year	Number of
1990	1359.95
1991	1442.8
1992	1533
1993	1630.44
1994	1737.18
1995	1855.54
1996	1980.39
1997	2118.51
1998	2271.08
1999	2438.41
2000	2622.67
2001	2846.4
2002	3094.42
2003	3368.34
2004	3670.99
2005	4006.7
2006	4206.46
2007	4420.05
2008	4645.69
2009	4878.23
2010	5117.79
2011	5422.97
2012	5734.83
2013	6060.66
2014	6403.91
2015	6768.24
2016	7139.05