Year	Number of
1990	321.23
1991	335.45
1992	306.11
1993	312.82
1994	335.91
1995	331.75
1996	300.32
1997	252.78
1998	234.25
1999	232.36
2000	235.02
2001	225.68
2002	227.95
2003	229.87
2004	226.36
2005	241.23
2006	236.33
2007	233.58
2008	226.33
2009	219.6
2010	223.34
2011	198.95
2012	200.86
2013	191.51
2014	199.81
2015	199.78
2016	197.85