Year	Number of
1990	233.21
1991	241.27
1992	231.74
1993	247.86
1994	251.98
1995	250.86
1996	241.15
1997	230.47
1998	230.8
1999	221.56
2000	219.88
2001	228.88
2002	221.47
2003	222.49
2004	219.26
2005	225.53
2006	229.47
2007	232.57
2008	233.02
2009	203.87
2010	205.22
2011	201.3
2012	190.22
2013	183.33
2014	168.21
2015	169.08
2016	166.98