Year	Number
1987	0.6989853439
1988	0.7324869325
1989	0.7659885211
1990	0.7994901097
1991	0.8329916983
1992	0.8664932869
1993	0.8999948755
1994	0.9334964641
1995	0.9669980527
1996	1.0004996413
1997	1.0340012299
1998	1.0675028185
1999	1.1010044071
2000	1.1094997324
2001	1.1179950577
2002	1.126490383
2003	1.1349857083
2004	1.1434810336
2005	1.1519763589
2006	1.1604716841
2007	1.1689670094
2008	1.1770011274
2009	1.1770011274
2010	1.1770011274
2011	1.1770011274
2012	1.1770011274
2013	1.1770011274
2014	1.1770011274
2015	1.1770011274
2016	1.1770011274
2017	1.1770011274
2018	1.1770011274
2019	1.1770011274
2020	1.1770011274