Year	Number of
1990	142.22
1991	148.67
1992	155.6
1993	163.47
1994	171.34
1995	179.08
1996	185.69
1997	192.78
1998	198.44
1999	204.76
2000	211.99
2001	219.54
2002	227.34
2003	236.53
2004	246.02
2005	256.69
2006	267.74
2007	279.18
2008	291.62
2009	304.98
2010	319.8
2011	330.87
2012	344.19
2013	358.99
2014	374.51
2015	388.6
2016	403.46