Year	Number of
1990	184.24
1991	185.56
1992	187.57
1993	189.6
1994	191.93
1995	194.6
1996	202.97
1997	212.06
1998	222.08
1999	232.45
2000	243.72
2001	248.39
2002	253.14
2003	259.09
2004	265.1
2005	271.08
2006	273.39
2007	275.56
2008	276.51
2009	277.53
2010	279.16
2011	280.63
2012	282.95
2013	283.93
2014	284.51
2015	284.46
2016	285.14