Year	Number of
1990	282.06
1991	287.08
1992	286.82
1993	286.39
1994	285.8
1995	289.35
1996	297.23
1997	310.41
1998	317.75
1999	323.55
2000	320.15
2001	322.15
2002	325.95
2003	328.94
2004	324
2005	322.54
2006	320.73
2007	320.95
2008	317.37
2009	308.14
2010	309.64
2011	309.21
2012	307.05
2013	309.06
2014	306.03
2015	303.29
2016	300.93