Year	Number of
1990	71.49
1991	75.64
1992	80.18
1993	85.16
1994	90.5
1995	96.25
1996	100.33
1997	104.69
1998	109.54
1999	114.63
2000	120.04
2001	124.1
2002	128.34
2003	133.04
2004	137.97
2005	143.21
2006	147.55
2007	151.91
2008	156.86
2009	161.93
2010	167.2
2011	171.13
2012	175.38
2013	180.17
2014	185.15
2015	190.28
2016	195.64