Year	Number of
1990	297.55
1991	292.68
1992	297.34
1993	298.59
1994	306.16
1995	302.52
1996	289.09
1997	278.83
1998	277.21
1999	261.18
2000	244.62
2001	231.48
2002	226.97
2003	223.61
2004	220.35
2005	222.79
2006	221.79
2007	218.44
2008	213.25
2009	200.87
2010	196.8
2011	196.51
2012	195.18
2013	193.4
2014	194.48
2015	197.11
2016	198.39