Year % 1990 14.7869674185464 1991 14.8456057007126 1992 14.9132947976879 1993 15.0513112884835 1994 15.0622876557191 1995 15.2505446623094 1996 15.3688524590164 1997 15.4589371980676 1998 15.5677655677656 1999 15.5516941789748 2000 15.4987633965375 2001 15.546875 2002 15.5261221486387 2003 15.5862068965517 2004 15.6572164948454 2005 15.634395670475 2006 15.6917885264342 2007 15.7451290152712 2008 15.7608695652174 2009 15.7845868152275 2010 15.83552055993 2011 15.8264462809917 2012 15.8761270090161 2013 15.9073935772965 2014 15.9195199435228 2015 15.9538357094365 2016 15.9443725743855 2017 16.0025101976781 2018 16.0244648318043 2019 15.981335666375 2020 16.0250926717993 2021 16.0598362969235 2022 16.1009817671809