Year	Number of
1990	4174.75
1991	4305.33
1992	4411.81
1993	4576.17
1994	4712.9
1995	4836.37
1996	4976.41
1997	5120.52
1998	5283.3
1999	5432.34
2000	5525.41
2001	5607.81
2002	5721.82
2003	5846.55
2004	5901.96
2005	5983.74
2006	6034.18
2007	6132.1
2008	6201.52
2009	6235.64
2010	6294.44
2011	6412.53
2012	6508.8
2013	6511.83
2014	6522.69
2015	6596.55
2016	6698.77