Year	Number of
1990	6417.1
1991	6625.47
1992	6836.39
1993	7055.52
1994	7284.59
1995	7529.56
1996	7778.41
1997	8033.85
1998	8300.66
1999	8582.63
2000	8886.3
2001	9131.93
2002	9382.6
2003	9641.59
2004	9915.27
2005	10208.06
2006	10545.85
2007	10895.23
2008	11263.3
2009	11647.77
2010	12052.27
2011	12565.48
2012	13091.06
2013	13619.27
2014	14179.26
2015	14781.11
2016	15473.99