Year	Number of
1990	219.93
1991	232.62
1992	249.62
1993	269.55
1994	289.12
1995	307.78
1996	317.13
1997	323.97
1998	330.01
1999	338.22
2000	349.63
2001	360.6
2002	375.34
2003	392.84
2004	410.86
2005	428.56
2006	448.35
2007	467.99
2008	488.73
2009	510.53
2010	535.26
2011	558.65
2012	586.35
2013	616.71
2014	647.51
2015	678.62
2016	711.74