Year	Number of
1990	4176.93
1991	4393.48
1992	4632.07
1993	4919.94
1994	5238.42
1995	5595.31
1996	5908.84
1997	6417.79
1998	6838.11
1999	7300.27
2000	7791.97
2001	7947.51
2002	8165.5
2003	8342.52
2004	8533.48
2005	8736.33
2006	8862.51
2007	8969.74
2008	9085.84
2009	9223.83
2010	9383.79
2011	9602.06
2012	9853.65
2013	10140.99
2014	10434.46
2015	10765.49
2016	11079.98