Year	Number of
1990	71.76
1991	72.84
1992	73.67
1993	74.4
1994	72.37
1995	70.35
1996	69.13
1997	69.67
1998	71.75
1999	73.9
2000	77.25
2001	77.55
2002	77.01
2003	78.7
2004	80.16
2005	81.54
2006	81.42
2007	80.73
2008	79.08
2009	80.15
2010	79.78
2011	81.44
2012	81.78
2013	79.62
2014	76.86
2015	75.93
2016	75.93