Year	Number of
1990	326.05
1991	337.56
1992	361.68
1993	374.48
1994	374.63
1995	352.19
1996	340.89
1997	321.56
1998	314.09
1999	315.68
2000	307.46
2001	308.76
2002	306.2
2003	313
2004	319.43
2005	332.61
2006	339.31
2007	335.56
2008	343.04
2009	341.46
2010	335.51
2011	333.62
2012	321.67
2013	309.55
2014	308.82
2015	313.18
2016	304.59