Year	Ratio
1971-01-01	0.794870018959045
1972-01-01	0.796140015125275
1973-01-01	0.793070018291473
1974-01-01	0.790050029754639
1975-01-01	0.792010009288788
1976-01-01	0.805169999599457
1977-01-01	0.821280002593994
1978-01-01	0.851639986038208
1979-01-01	0.876929998397827
1980-01-01	0.890439987182617
1981-01-01	0.920799970626831
1982-01-01	0.942990005016327
1983-01-01	0.984899997711182
1984-01-01	0.992030024528503
1985-01-01	0.991209983825684
1986-01-01	0.978439986705780
1987-01-01	0.964680016040802
1988-01-01	0.956539988517761
1989-01-01	0.959869980812073
1990-01-01	0.975969970226288
1991-01-01	0.978009998798370
1992-01-01	0.984279990196228
1993-01-01	1.013120055198670
1994-01-01	0.962830007076263
1995-01-01	1.013980031013490
1996-01-01	1.025910019874570
1997-01-01	1.035400032997130
1998-01-01	1.038740038871770
1999-01-01	1.038079977035520
2000-01-01	1.056319952011110
2001-01-01	1.042829990386960
2002-01-01	1.013239979743960
2003-01-01	1.001279950141910
2004-01-01	0.982829988002777
2005-01-01	0.954089999198914
2006-01-01	0.947480022907257
2007-01-01	0.925369977951050
2010-01-01	0.938759982585907
2011-01-01	0.956929981708527
2012-01-01	0.957679986953735
2013-01-01	0.960039973258972
2014-01-01	0.944339990615845
2015-01-01	0.934099972248077