Year	Number of
1990	9634.25
1991	9937.47
1992	10253.66
1993	10596.8
1994	10893.99
1995	11225.77
1996	11538.04
1997	11930.65
1998	12347.47
1999	12803.48
2000	13269.93
2001	13647.47
2002	14001.58
2003	14351.64
2004	14689.68
2005	15067.97
2006	15325.89
2007	15689.98
2008	16054.47
2009	16473.1
2010	16899.62
2011	17350.77
2012	17883.18
2013	18440.54
2014	19044.48
2015	19719.09
2016	20441.08