Year Ratio 1971-01-01 1.126049995422360 1972-01-01 1.178030014038090 1973-01-01 1.028920054435730 1974-01-01 1.013299942016600 1975-01-01 0.986370027065277 1976-01-01 1.001760005950930 1977-01-01 1.004529953002930 1978-01-01 1.006960034370420 1979-01-01 1.008880019187930 1980-01-01 1.014400005340580 1981-01-01 1.081869959831240 1982-01-01 1.023699998855590 1983-01-01 1.015969991683960 1984-01-01 1.004670023918150 1985-01-01 1.001209974288940 1986-01-01 0.984160006046295 1987-01-01 0.967000007629395 1988-01-01 0.953279972076416 1989-01-01 0.932219982147217 1990-01-01 0.947350025177002 1991-01-01 0.947749972343445 1992-01-01 0.932359993457794 1993-01-01 0.926519989967346 1997-01-01 0.930060029029846 1999-01-01 0.946129977703094 2000-01-01 0.968400001525879 2001-01-01 0.954469978809357 2002-01-01 0.968970000743866 2003-01-01 0.950060009956360 2004-01-01 0.947979986667633 2005-01-01 0.955399990081787 2006-01-01 0.919730007648468 2007-01-01 0.949570000171661