Year	Number of
1990	145.97
1991	157.2
1992	169.13
1993	182.17
1994	196.36
1995	211.96
1996	233.53
1997	257.62
1998	285.2
1999	315.62
2000	349.24
2001	373.38
2002	399.46
2003	428.8
2004	460.29
2005	494.2
2006	511.27
2007	529.04
2008	548.47
2009	568.74
2010	590.03
2011	608.44
2012	627.66
2013	647.33
2014	668.34
2015	690.86
2016	713.1