Year	Number of
1990	337.26
1991	344.84
1992	351.91
1993	358.19
1994	364.7
1995	372.47
1996	373.84
1997	377.1
1998	379.69
1999	382.99
2000	386.7
2001	392.79
2002	399.07
2003	404.7
2004	410.55
2005	416.96
2006	414.42
2007	412.79
2008	410.91
2009	408.97
2010	407.52
2011	415.94
2012	425.27
2013	433.61
2014	444.11
2015	455.03
2016	466.55