Year	Number of
1990	220.08
1991	230.87
1992	243.23
1993	256.76
1994	270.69
1995	284.83
1996	297.63
1997	310.26
1998	322.96
1999	336.34
2000	350.95
2001	366.77
2002	383.87
2003	402.47
2004	422.37
2005	443.77
2006	463.48
2007	484.49
2008	507.31
2009	531.39
2010	556.9
2011	582.48
2012	609.32
2013	637.45
2014	667.75
2015	700.65
2016	736.73