Year % 1982 10.9200003306071 1983 11.6200003517998 1984 11.4800003475613 1985 11.0600003348456 1986 11.9000003602769 1987 10.64000032213 1988 9.380000283983 1989 10.64000032213 1990 10.64000032213 1991 12.6500000953674 1992 12.7000000476837 1993 12.6758596545235 1994 13.1467623059324 1995 12.695846968362 1996 12.2591910606266 1997 11.9825861100038 1998 12.1951114740288 1999 12.071877641383 2000 12.1715539440033 2001 11.6243803976043 2002 11.387913378312 2003 12.8219814495275 2004 11.9643907528209 2005 11.3939380792616 2006 10.8905898841823 2007 10.4385350357948 2008 10.4291009360419 2009 10.0653700920516 2010 10.9993475073677 2011 10.9144525231277 2012 10.1571966422671 2013 9.95235329417181 2014 10.0718377079627 2015 9.83508333333333 2016 9.575 2017 9.31 2018 8.976532 2019 8.61132908333333 2020 7.68383775 2021 7.39227225 2022 7.31490375 2023 6.6989575