Year	Number of
1990	122.83
1991	130.45
1992	138.75
1993	148.22
1994	159.1
1995	171.76
1996	180.78
1997	190.97
1998	202.33
1999	209.42
2000	217.33
2001	228.57
2002	239.35
2003	250.58
2004	261.78
2005	272.52
2006	282.47
2007	293.45
2008	306.61
2009	320.36
2010	334.98
2011	348.13
2012	362.86
2013	377.99
2014	394.21
2015	412.08
2016	430.04