Year Index 1988 6.569 1989 7.758 1990 10.35 1991 13.682 1992 16.637 1993 20.148 1994 24.419 1995 31.33 1996 37.52 1997 44.44 1998 49.02 1999 54.5 2000 59.99 2001 64.08 2002 67.17 2003 70.97 2004 74.89 2005 77.39 2006 82.45 2007 88.53 2008 91.63 2009 96.72 2010 101.24 2011 105.36 2012 110.62 2013 111.08 2014 110.05 2015 111.028 2016 113.075 2017 115.495 2018 118.67 2019 122.765 2020 126.497 2021 130.277 2022 134.238 2023 138.251 2024 142.455