Year	Number of
1990	308.46
1991	303.18
1992	299.42
1993	298.58
1994	294.88
1995	293.45
1996	290.53
1997	294.09
1998	295.74
1999	304.44
2000	307.88
2001	309.26
2002	308.67
2003	307.77
2004	314.75
2005	309.84
2006	306.77
2007	308.43
2008	306.09
2009	305.42
2010	300.2
2011	298.97
2012	303.08
2013	306.88
2014	302.58
2015	308.92
2016	307.29