Year	Number of
1990	6531.61
1991	6876.76
1992	7245.35
1993	7624.76
1994	8023.13
1995	8466.89
1996	8752.36
1997	9063.08
1998	9405.42
1999	9762.02
2000	10139.34
2001	10550.39
2002	10992.92
2003	11455.31
2004	11965.23
2005	12519.88
2006	12931.65
2007	13392.23
2008	13872.09
2009	14370.3
2010	14871.46
2011	15438.22
2012	16051.26
2013	16644.8
2014	17244.44
2015	17850.27
2016	18465.24