Year	Number of
1990	1607.44
1991	1734.25
1992	1874.7
1993	2029.88
1994	2199.62
1995	2385.39
1996	2487.76
1997	2594.85
1998	2709.07
1999	2830.3
2000	2960.25
2001	3123.73
2002	3298.59
2003	3486.68
2004	3686.54
2005	3900.24
2006	4149.35
2007	4413.49
2008	4698.44
2009	5000.99
2010	5323.92
2011	5623.84
2012	5941.02
2013	6276.1
2014	6628.5
2015	6999.12
2016	7381.8