Year	Number of
1990	6006.62
1991	6316.64
1992	6617.01
1993	6871.1
1994	7149.64
1995	7485.31
1996	7766.84
1997	8116.81
1998	8593.9
1999	9017.42
2000	9500.25
2001	9959.09
2002	10478.9
2003	11082.95
2004	11313.86
2005	11609.57
2006	11953.79
2007	12285.78
2008	12651.29
2009	13046.17
2010	13482.23
2011	13902.31
2012	14323.75
2013	14721.39
2014	15107.01
2015	15664.44
2016	16137.57