Year	Number of
1990	119.24
1991	123.98
1992	128.72
1993	136.57
1994	143.97
1995	152.56
1996	161.08
1997	172.12
1998	184.21
1999	196.3
2000	210.65
2001	226.74
2002	243.64
2003	260.21
2004	276.59
2005	292.69
2006	303.34
2007	313.99
2008	327.62
2009	343.05
2010	360.98
2011	378.44
2012	397.43
2013	416.84
2014	436.33
2015	454.39
2016	469.01