Year	Number of
1990	84.55
1991	85.34
1992	85.34
1993	84.91
1994	84.72
1995	85.23
1996	86.94
1997	89.56
1998	92.92
1999	96.65
2000	100.51
2001	107.79
2002	115.5
2003	123.81
2004	132.49
2005	141.64
2006	146.49
2007	151.26
2008	156.83
2009	162.67
2010	168.86
2011	173
2012	177.53
2013	182.43
2014	187.82
2015	193.75
2016	199.02