Year annual % 1961 2.67750780003869 1962 2.44696001938284 1963 2.19182647239121 1964 2.24113327435576 1965 2.57084686962757 1966 2.80880785102243 1967 3.01560768660481 1968 3.12164160228976 1969 3.11505640418176 1970 3.08818394838363 1971 3.00931354381668 1972 2.94896268963442 1973 2.95206833272967 1974 2.93537515995271 1975 2.9070836928786 1976 2.89089391293466 1977 2.86390960667022 1978 2.85847530507977 1979 3.04977646065132 1980 3.35547032700799 1981 3.63825218024574 1982 3.80282951759302 1983 3.5877838789899 1984 3.3123358772293 1985 3.40883127197502 1986 3.62060755685165 1987 3.59766169671716 1988 3.18725478939529 1989 2.66757702027772 1990 2.4615927974137 1991 2.23868589939967 1992 2.26554307510296 1993 3.18151530970022 1994 -16.0491526157981 1995 -16.8806296708643 1996 16.6255019779963 1997 13.2470672505578 1998 3.18243918155598 1999 1.19243584222433 2000 1.24573125745531 2001 1.39530227863448 2002 1.78798197593577 2003 2.31040451162765 2004 2.57920977781251 2005 2.63169301631945 2006 2.66480719140037 2007 2.6937067262308 2008 2.68159866469225 2009 2.64057029628242 2010 2.6071051025344 2011 2.56550960901795 2012 2.45984040638473 2013 2.3792915199656 2014 2.3775340228914 2015 2.38595568459796 2016 2.44299698959529 2017 2.47880785239257 2018 2.43503841544025 2019 2.39079436618151 2020 2.3967070500013 2021 2.3717515483557 2022 2.31160323907511 2023 2.28190198384881