Year annual % growth 1971 11.181271593125715 1972 4.5906156161131975 1973 13.362095739139377 1974 -3.922391499549221 1975 5.91255205702555 1976 -16.330465507572043 1977 -12.717555092899232 1978 -11.380905546148597 1979 -0.5190696963192494 1980 46.99277312521383 1981 60.48719346171211 1982 52.546798070388235 1983 -13.63306989300959 1984 -0.6373994031542196 1985 -17.959115826242254 1986 -21.214057624033728 1987 -14.051620874407206 1988 -32.79585698422842 1989 -23.816279509459733 1990 4.671529802604482 1991 55.43151726827949 1992 6.659201863560199 1993 -28.03223078984368 1994 16.790708603609957 1995 -91.04140935371466 1996 34.379954844246214 1997 241.39983427884272 1998 66.01339320916082 1999 -19.33399994569602 2000 -95.41587905077847 2001 1491.620875127285 2002 40.64993276276164 2003 96.59513956830443 2004 -28.31913328743127 2005 41.53617459062443 2006 29.115838811172637 2007 9.492632954525789 2008 22.05238934990561 2009 25.914488506501826 2010 38.23065890276581 2011 -26.205911786648358 2012 66.20356586084034 2013 26.612528522378412 2014 12.931872660037328 2015 -15.82329679404694 2016 -20.103013418764718 2017 -30.45525851913041 2018 13.169610595314339 2019 -12.085628084438667 2020 -18.37501168450781 2021 35.666506642880904