Year	Number of
1990	116.82
1991	121.18
1992	125.98
1993	131.2
1994	136.81
1995	142.93
1996	144.93
1997	147.29
1998	149.95
1999	152.9
2000	156.22
2001	156.98
2002	158.06
2003	159.33
2004	160.71
2005	162.25
2006	165.45
2007	168.56
2008	171.93
2009	175.47
2010	179.35
2011	183.88
2012	188.81
2013	193.89
2014	199.26
2015	204.92
2016	210.89