Year	Number of
1990	262.69
1991	273.92
1992	286.15
1993	299.55
1994	313.81
1995	328.99
1996	341.71
1997	354.75
1998	368.54
1999	382.54
2000	396.96
2001	409.63
2002	422.88
2003	437.3
2004	452.92
2005	469.93
2006	485.33
2007	501.86
2008	519.74
2009	537.83
2010	555.95
2011	576.26
2012	597.32
2013	619.76
2014	643.74
2015	669.48
2016	694.44