Year	Number of
1990	206.44
1991	220.87
1992	239.58
1993	253.89
1994	270.44
1995	278.33
1996	289.61
1997	297.5
1998	293.31
1999	291.41
2000	288.37
2001	287.37
2002	294.16
2003	302.49
2004	304.81
2005	308.71
2006	311.3
2007	311.74
2008	313.79
2009	311.12
2010	312.69
2011	309.43
2012	315.33
2013	327.17
2014	332.8
2015	337.09
2016	342.2