Year Number 1982 0.4349717268 1983 0.5216462401 1984 0.6083207533 1985 0.6949952665 1986 0.7816697797 1987 0.8683442929 1988 0.9550188061 1989 1.0416933193 1990 1.1283678326 1991 1.2150423458 1992 1.301716859 1993 1.3883913722 1994 1.4750658854 1995 1.5617403986 1996 1.6484149119 1997 1.7350894251 1998 1.8217639383 1999 1.9084384515 2000 1.9682470639 2001 2.0165289256 2002 2.0648107873 2003 2.113092649 2004 2.1613745107 2005 2.2096563723 2006 2.2096563723 2007 2.2096563723 2008 2.2096563723 2009 2.2096563723 2010 2.2096563723 2011 2.2096563723 2012 2.2096563723 2013 2.2096563723 2014 2.2096563723 2015 2.2096563723 2016 2.2096563723 2017 2.2096563723 2018 2.2096563723 2019 2.2096563723 2020 2.2096563723