Year	Number of
1990	295.32
1991	294.76
1992	295.43
1993	298.71
1994	303.04
1995	308.96
1996	309.02
1997	304.93
1998	301.97
1999	296.27
2000	293.28
2001	290.16
2002	286.29
2003	288.42
2004	287.89
2005	287.12
2006	285.19
2007	283.68
2008	284.19
2009	285.33
2010	286.83
2011	288.91
2012	291.76
2013	294.81
2014	298.37
2015	302.68
2016	307.7