Year Index 2010=1, Trend 1978-01-01 0.237020215088058 1979-01-01 0.271948177457978 1980-01-01 0.319431209913417 1981-01-01 0.368584919379943 1982-01-01 0.409894482017326 1983-01-01 0.406696720655488 1984-01-01 0.409285336752918 1985-01-01 0.481962569202942 1986-01-01 0.562400698111821 1987-01-01 0.636134073192769 1988-01-01 0.665096453949213 1989-01-01 0.675472011393910 1990-01-01 0.692729239115943 1991-01-01 0.698559485532824 1992-01-01 0.691537813484644 1993-01-01 0.683215161673146 1994-01-01 0.699763570164318 1995-01-01 0.707362025277785 1996-01-01 0.729662295708136 1997-01-01 0.743944308575844 1998-01-01 0.752063839749636 1999-01-01 0.730863614666585 2000-01-01 0.714869068720304 2001-01-01 0.737220296264064 2002-01-01 0.749497840410944 2003-01-01 0.773551265472071 2004-01-01 0.800703917510077 2005-01-01 0.840996816570693 2006-01-01 0.881580535427300 2007-01-01 0.896305966203814 2008-01-01 0.948010391188538 2009-01-01 0.980259897776652 2010-01-01 1.000000000000000