Year annual % 1964 2.7999999989998 1965 0.389105059342261 1966 1.55038759593052 1967 2.0992366421952 1968 1.58878504672939 1969 3.49586016559325 1970 0.177777777777795 1971 4.47499999975001 1972 4.33117970783491 1973 16.5137614681954 1974 21.4370078736641 1975 34.5761063381485 1976 31.5586605641125 1977 11.3990111699532 1978 -1.58360185022085 1979 1.08156690288337 1980 4.16926655363289 1981 2.79898218829486 1982 1.02103960396038 1983 0.191424196019035 1984 -1.55903706534203 1985 -3.0587687291366 1986 -3.20333146472299 1987 -1.54711673699019 1988 0.907563025210514 1989 1.03264490339738 1990 2.07715133531159 1991 4.86111111111136 1992 -0.0770060064690777 1993 1.05579531442694 1994 0.564325478533144 1995 4.8684310305603 1996 1.22206988451309 1997 0.05715470377076 1998 -0.371269734983814 1999 -1.33376350229422 2000 -1.12499477854774 2001 -1.12094477457175 2002 0.24718651429923 2003 0.612194395125212 2004 0.515506766998081 2005 0.479230397826084 2006 2.20902407871182 2007 4.16782330119979 2008 9.87024791275994 2009 5.05722314693633 2010 5.33941680637454 2011 5.82621608838862 2012 2.86626887489915 2013 3.53252470694918 2014 2.23629031536978 2015 1.20607322150109 2016 2.06884036053473 2017 -0.838194579675018 2018 2.45814158007532 2019 -2.09333333333329 2020 3.44545825956692 2021 3.06328988941547 2022 2.4740737192537 2023 2.32708518362692