Year	Number of
1990	83.92
1991	87.57
1992	91.56
1993	94.16
1994	100.46
1995	102.9
1996	106.83
1997	110.79
1998	116
1999	123.81
2000	129.03
2001	135.75
2002	141.06
2003	146.7
2004	155.25
2005	163.26
2006	170.44
2007	177.02
2008	184.74
2009	191.87
2010	199
2011	205.79
2012	212.9
2013	220.64
2014	228.04
2015	236.43
2016	245.52