Year	Number of
1990	148.58
1991	159.75
1992	173.84
1993	189.56
1994	208.04
1995	224.74
1996	236.78
1997	247.13
1998	258.96
1999	272.1
2000	279.68
2001	284.33
2002	292.42
2003	294.52
2004	298.82
2005	303.23
2006	315.8
2007	329.24
2008	341.62
2009	358.46
2010	376.66
2011	386.42
2012	398.8
2013	410.32
2014	423.01
2015	436.23
2016	450.1