Year	Number of
1990	7814.25
1991	8092.12
1992	8345.16
1993	8609.41
1994	8897.02
1995	9152.57
1996	9411.92
1997	9733.84
1998	10066.07
1999	10474.4
2000	10902.9
2001	11306.6
2002	11778.72
2003	12324.58
2004	12892.52
2005	13544.12
2006	14093.54
2007	14687.08
2008	15341.02
2009	15925.31
2010	16535.55
2011	17205.36
2012	17880.85
2013	18491.65
2014	19225.01
2015	19989.47
2016	20953.57