Year	Number of
1990	96.68
1991	99.67
1992	102.78
1993	106.24
1994	109.63
1995	113.51
1996	116.83
1997	120.79
1998	125.26
1999	130.47
2000	135.54
2001	140.22
2002	145.32
2003	150.97
2004	156.69
2005	163.17
2006	169.01
2007	175.2
2008	182.59
2009	190.32
2010	198.12
2011	205.48
2012	213.58
2013	222.09
2014	231.66
2015	240.88
2016	249.03