Year	Number of
1990	168.68
1991	175.87
1992	184.81
1993	193.42
1994	200.94
1995	208.86
1996	217.73
1997	225.67
1998	236.69
1999	242.35
2000	253.51
2001	251.92
2002	255.67
2003	261.53
2004	266.53
2005	271.64
2006	278.34
2007	284.53
2008	295.5
2009	307.33
2010	317.92
2011	330.12
2012	344.02
2013	356.31
2014	370.8
2015	386.53
2016	402.77