Year	Number of
1990	124.95
1991	131.49
1992	138.09
1993	144.83
1994	152.91
1995	162.2
1996	170.31
1997	178.76
1998	186.51
1999	195.5
2000	204.88
2001	216.3
2002	227.5
2003	239.18
2004	251.2
2005	263.83
2006	278.05
2007	291.8
2008	306.65
2009	321.63
2010	336.49
2011	352.49
2012	367.55
2013	382.65
2014	396.07
2015	407.85
2016	426.52