Year	Number of
1990	231.46
1991	241.25
1992	253.9
1993	264.93
1994	272.2
1995	272
1996	276.57
1997	279.98
1998	283.55
1999	293.92
2000	303.24
2001	309.96
2002	315.19
2003	323.62
2004	331.94
2005	332.84
2006	334.8
2007	341.02
2008	344
2009	346.33
2010	351.55
2011	359.96
2012	369.05
2013	382.84
2014	398.33
2015	415.16
2016	433.18