Year	Number of
1990	53
1991	54.17
1992	53.48
1993	54.73
1994	55.98
1995	57.64
1996	59.34
1997	60.81
1998	60.59
1999	61.11
2000	62.43
2001	63.64
2002	64.1
2003	65.03
2004	66.11
2005	68.31
2006	70.05
2007	71.64
2008	70.94
2009	71.84
2010	74.52
2011	76.68
2012	78.57
2013	81.49
2014	83.14
2015	84.63
2016	89.02