Year	Number of
1990	94.65
1991	96.35
1992	99.24
1993	102.61
1994	106.43
1995	110.63
1996	113.29
1997	117.01
1998	119.25
1999	122.35
2000	123.7
2001	124.94
2002	126.28
2003	130.72
2004	134.11
2005	137.86
2006	141.95
2007	146.74
2008	152.01
2009	157.3
2010	161.95
2011	166.97
2012	173.77
2013	179.95
2014	186.82
2015	194.13
2016	203.98