Year	Number of
1990	133.09
1991	137.22
1992	141.43
1993	145.73
1994	150.41
1995	155.74
1996	163.96
1997	172.68
1998	181.66
1999	191.23
2000	201.63
2001	213.25
2002	225.52
2003	238.45
2004	252.62
2005	268.08
2006	278.44
2007	288.51
2008	298.56
2009	308.94
2010	319.71
2011	329.22
2012	339.01
2013	348.42
2014	358.05
2015	367.5
2016	377.9