Year	Number of
1990	199.18
1991	209.66
1992	222.19
1993	238.89
1994	252.71
1995	266.46
1996	280.17
1997	289.46
1998	296.38
1999	304.22
2000	309.7
2001	316.81
2002	324.93
2003	335.12
2004	346.46
2005	365.48
2006	381.75
2007	392.51
2008	409.18
2009	425.95
2010	442.32
2011	458.83
2012	475.58
2013	492.81
2014	510.87
2015	531.07
2016	550.39