Year	Number of
1990	182.74
1991	193.81
1992	208.52
1993	224.65
1994	241.52
1995	261.98
1996	266.77
1997	269
1998	274.55
1999	279.27
2000	285.38
2001	287.17
2002	286.9
2003	287.46
2004	290.64
2005	289.76
2006	294.78
2007	297.65
2008	302.06
2009	307.02
2010	314.07
2011	320.13
2012	326.95
2013	333.35
2014	339.38
2015	345.59
2016	352