Year	Number of
1990	112.4
1991	114.5
1992	118.02
1993	120.81
1994	123.78
1995	126.4
1996	130.95
1997	133.44
1998	136.36
1999	141.26
2000	147.76
2001	153.61
2002	158.79
2003	161.79
2004	163.53
2005	167.15
2006	170.12
2007	174.8
2008	179.54
2009	181.8
2010	185.71
2011	191.24
2012	198.7
2013	208.05
2014	210.54
2015	213.23
2016	217.03