Year	Number of
1990	4123.23
1991	4284.59
1992	4487.09
1993	4670.6
1994	4923.28
1995	5194.46
1996	5423.3
1997	5675.28
1998	5943.81
1999	6315.28
2000	6665.41
2001	6936.09
2002	7245.55
2003	7625.62
2004	7997.98
2005	8378.53
2006	8725.85
2007	9061.95
2008	9405.32
2009	9748.34
2010	10134.83
2011	10516.51
2012	10895.58
2013	11282.56
2014	11726.22
2015	12150.22
2016	12440.37