Year	Number of
1990	143.49
1991	150.57
1992	160.25
1993	171.26
1994	184.57
1995	195.4
1996	201.99
1997	209.81
1998	218.19
1999	226.68
2000	232.16
2001	235.82
2002	242.59
2003	244.16
2004	246.82
2005	250.18
2006	254.74
2007	261.05
2008	268.04
2009	277.32
2010	287.14
2011	292.18
2012	298.68
2013	303.22
2014	308.05
2015	313.89
2016	320.13