Year	Number of
1990	132.21
1991	133.33
1992	134.34
1993	136.08
1994	140.55
1995	145.96
1996	153.12
1997	161.98
1998	173.8
1999	184.95
2000	196.86
2001	207.69
2002	218.07
2003	227.24
2004	234.72
2005	241.97
2006	251.69
2007	261.7
2008	270.68
2009	278.01
2010	284.05
2011	289.17
2012	294.26
2013	300.08
2014	302.08
2015	303.71
2016	306.24