Year	Number of
1990	1471.8
1991	1516.14
1992	1570.32
1993	1646.91
1994	1729.35
1995	1818.65
1996	1851.21
1997	2083.14
1998	2283.18
1999	2522.04
2000	2777.22
2001	2773.52
2002	2811.17
2003	2843.84
2004	2886.11
2005	2932.08
2006	2951.17
2007	2965.26
2008	2985.83
2009	3008.16
2010	3039.27
2011	3062.88
2012	3092.02
2013	3125.19
2014	3153.83
2015	3184.68
2016	3220.99