Year	Number of
1990	10219.28
1991	10680.72
1992	11173.44
1993	11628.33
1994	12085.64
1995	12566.42
1996	12989.08
1997	13402.01
1998	13843.76
1999	14217.24
2000	14518.3
2001	14843.91
2002	15147.13
2003	15496.34
2004	15992.37
2005	16591.57
2006	17015.77
2007	17428.47
2008	17791.62
2009	18073.08
2010	18440.47
2011	18771.63
2012	19528.79
2013	20078.67
2014	20340.83
2015	20876.13
2016	21451.78