Year annual % 1961 2.02259973279057 1962 2.17556040717112 1963 2.25833856168216 1964 2.37335843320943 1965 2.3467386018567 1966 2.3391785122375 1967 1.64186215165934 1968 0.788368905854224 1969 0.719492266502827 1970 1.83800956713655 1971 3.23753715250208 1972 3.61364176347744 1973 2.98650448071879 1974 0.960210528002221 1975 -0.435316687280262 1976 -0.540842804073148 1977 -0.607953236416106 1978 -0.611671927217687 1979 -0.704827319369108 1980 -0.3910073407843 1981 1.08776135453403 1982 2.23544355783694 1983 2.39490364946368 1984 2.48185698421507 1985 2.56110201253732 1986 2.46854620975237 1987 2.29033832706748 1988 2.23222011639668 1989 2.1968506588625 1990 2.22157896887967 1991 2.24365277511788 1992 2.30069558778237 1993 2.32223874299347 1994 2.35304974101942 1995 2.58409269476565 1996 2.99384141000332 1997 3.1366195099622 1998 2.98818970790555 1999 2.76225974011357 2000 1.76959560691815 2001 0.515751762652575 2002 0.115930353970459 2003 0.145981753039584 2004 0.135722744336851 2005 -0.382505876810364 2006 -1.0747885465001 2007 -1.29795332493524 2008 -1.37259095767935 2009 -1.45541484875174 2010 -1.53083329873194 2011 -1.63135754915238 2012 -1.62497357703192 2013 -0.788793214612497 2014 -0.0505603785945698 2015 -0.0112391121219639 2016 0.123560813249084 2017 0.117802162109984 2018 0.151256296169056 2019 0.290665380719677 2020 0.312082286285984 2021 0.288921192202971 2022 0.171845159947773 2023 0.0166145155866348