Year Index 2010=1, Trend 1970-01-01 0.378093544544013 1971-01-01 0.411383225172952 1972-01-01 0.437411403835981 1973-01-01 0.469387608096271 1974-01-01 0.511939653856296 1975-01-01 0.544703871354457 1976-01-01 0.556527302190910 1977-01-01 0.575969381961141 1978-01-01 0.597226581601119 1979-01-01 0.630162071265423 1980-01-01 0.670042206126100 1981-01-01 0.700732460289938 1982-01-01 0.731266827504596 1983-01-01 0.737159397883149 1984-01-01 0.742862873424729 1985-01-01 0.749211659865347 1986-01-01 0.773385298032925 1987-01-01 0.796012114995921 1988-01-01 0.799579935120082 1989-01-01 0.803694449675397 1990-01-01 0.823404746896313 1991-01-01 0.853438247414493 1992-01-01 0.917979347427901 1993-01-01 0.959501602740263 1994-01-01 0.961138321239611 1995-01-01 0.979543635971266 1996-01-01 0.987558933033477 1997-01-01 0.970483331789964 1998-01-01 0.970280122963536 1999-01-01 0.975502363625486 2000-01-01 0.975038545004469 2001-01-01 0.980248982042060 2002-01-01 0.984194431494227 2003-01-01 0.986833730531726 2004-01-01 0.973333352842932 2005-01-01 0.961631027749674 2006-01-01 0.942545665088236 2007-01-01 0.935786657846335 2008-01-01 0.956975916305681 2009-01-01 0.991546250759502 2010-01-01 1.000000000000000