Year	Number of
1990	148.09
1991	150.65
1992	159.51
1993	167.73
1994	176.63
1995	184.39
1996	191.83
1997	196.81
1998	203.98
1999	211.11
2000	217.36
2001	225.56
2002	236.02
2003	243.69
2004	250.01
2005	257.78
2006	268.92
2007	275.89
2008	285.8
2009	296.21
2010	307.25
2011	315.53
2012	328.41
2013	346.29
2014	356.61
2015	366.45
2016	374.86