Year	Number
1985	0.8252063016
1986	0.8613465866
1987	0.8974868717
1988	0.9336271568
1989	0.9697674419
1990	1.0059077269
1991	1.0421980495
1992	1.0784883721
1993	1.1147786947
1994	1.1510690173
1995	1.1259511306
1996	1.100833244
1997	1.0757153574
1998	1.0505974708
1999	1.0254795842
2000	1.0003616976
2001	0.975243811
2002	0.975243811
2003	0.975243811
2004	0.975243811
2005	0.975243811
2006	0.975243811
2007	0.975243811
2008	0.975243811
2009	0.975243811
2010	0.975243811
2011	0.975243811
2012	0.975243811
2013	0.975243811
2014	0.975243811
2015	0.975243811
2016	0.975243811
2017	0.975243811
2018	0.975243811
2019	0.975243811
2020	0.975243811