Year	Number of
1990	6395
1991	6673.36
1992	6923.89
1993	7226.38
1994	7540.49
1995	7890.54
1996	8366.25
1997	8905.17
1998	9374.58
1999	9872.95
2000	10390.5
2001	10944.14
2002	11498.54
2003	12057.43
2004	12584.63
2005	13504.43
2006	14050.81
2007	14815.35
2008	15437.59
2009	16172.22
2010	16958.18
2011	17623.18
2012	18317.36
2013	19220.41
2014	19975.6
2015	20793.27
2016	21604.36