Year	Number of
1990	96.87
1991	103.4
1992	110.49
1993	118.31
1994	126.74
1995	135.83
1996	144.05
1997	152.84
1998	162.67
1999	173.1
2000	184.21
2001	192.83
2002	201.86
2003	211.92
2004	222.57
2005	233.87
2006	244.56
2007	255.55
2008	267.79
2009	280.43
2010	293.57
2011	307.06
2012	321.35
2013	337.1
2014	353.57
2015	370.72
2016	388.83