Year	Number of
1990	113.83
1991	119.57
1992	125.21
1993	130.82
1994	136.64
1995	142.92
1996	147.25
1997	152.01
1998	157.27
1999	162.98
2000	169.24
2001	173.44
2002	178.29
2003	183.59
2004	189.28
2005	195.43
2006	200.87
2007	206.54
2008	212.65
2009	219.2
2010	226.31
2011	232.57
2012	239.38
2013	246.47
2014	254.03
2015	262.06
2016	270.22