Year	Number of
1990	5643.36
1991	5839.59
1992	6051.13
1993	6244.05
1994	6439.7
1995	6658.21
1996	6901.27
1997	7124.38
1998	7429.74
1999	7739.23
2000	8115.84
2001	8322.45
2002	8529.53
2003	8735.16
2004	8897.95
2005	9126.2
2006	9772.08
2007	10350.39
2008	10907.69
2009	11468.29
2010	11965.44
2011	12204.47
2012	12438.06
2013	12634.79
2014	12897.03
2015	13177.68
2016	13482.99