Year	Ratio
1971-01-01	0.850099980831146
1972-01-01	0.864570021629334
1973-01-01	0.883589982986450
1974-01-01	0.897660017013550
1975-01-01	0.911949992179871
1976-01-01	0.929099977016449
1977-01-01	0.945689976215363
1978-01-01	0.959100008010864
1979-01-01	0.979290008544922
1980-01-01	0.998709976673126
1981-01-01	1.011299967765810
1982-01-01	1.010939955711360
1983-01-01	1.025769948959350
1984-01-01	1.025660037994380
1985-01-01	1.052449941635130
1986-01-01	1.005470037460330
1987-01-01	1.012380003929140
1988-01-01	1.035509943962100
1989-01-01	1.006940007209780
1990-01-01	1.001850008964540
1991-01-01	1.005959987640380
1992-01-01	1.014430046081540
1993-01-01	1.012060046195980
1994-01-01	1.013370037078860
1995-01-01	1.005570054054260
1996-01-01	1.014050006866460
1998-01-01	1.007809996604920
1999-01-01	1.012099981307980
2000-01-01	1.010589957237240
2002-01-01	1.006459951400760
2003-01-01	1.009639978408810
2004-01-01	1.010079979896550