Year	Number of
1990	436.28
1991	433.65
1992	429.97
1993	425.25
1994	425.62
1995	416.19
1996	405.78
1997	394.76
1998	384.41
1999	372.59
2000	370.42
2001	367.54
2002	364.07
2003	368.06
2004	367.44
2005	369.4
2006	376.98
2007	383.59
2008	391.96
2009	395.85
2010	401.18
2011	408.15
2012	413.07
2013	412.95
2014	420.56
2015	423.56
2016	428.92