Year	Number of
1990	113.54
1991	116.45
1992	119.63
1993	123.07
1994	126.66
1995	130.52
1996	134.33
1997	138.19
1998	141.97
1999	145.81
2000	149.92
2001	153.34
2002	156.91
2003	160.64
2004	164.5
2005	168.72
2006	172.21
2007	175.75
2008	179.8
2009	184.12
2010	188.83
2011	192.9
2012	197.12
2013	201.02
2014	205.24
2015	209.85
2016	216.6