Year	Number of
1990	108.89
1991	100.49
1992	91.45
1993	81.79
1994	74.56
1995	69.4
1996	65.1
1997	63.22
1998	61.28
1999	60.89
2000	61.06
2001	62.02
2002	63.63
2003	66.12
2004	69.04
2005	72.71
2006	73.62
2007	75.27
2008	77.09
2009	78.88
2010	80.95
2011	82.52
2012	84.5
2013	86.63
2014	89.18
2015	92.12
2016	95.66