Year	Number of
1990	518.02
1991	515.42
1992	518.07
1993	512.9
1994	513.16
1995	499.05
1996	462.9
1997	429.03
1998	400.07
1999	381.47
2000	361.39
2001	357.77
2002	366.17
2003	367.33
2004	364.46
2005	368.02
2006	372.91
2007	367.31
2008	357.77
2009	354.89
2010	351.72
2011	353.14
2012	356.66
2013	358.36
2014	356.74
2015	352.45
2016	360.3