Year	Number of
1990	492.82
1991	478.93
1992	467.43
1993	457.46
1994	448.5
1995	440.47
1996	445.91
1997	452.6
1998	460.34
1999	469.46
2000	480.45
2001	487.51
2002	496.5
2003	506.96
2004	518.77
2005	532.18
2006	543.81
2007	556.23
2008	570.16
2009	584.98
2010	601.12
2011	614.38
2012	629.12
2013	644.84
2014	661.94
2015	680.63
2016	700.38