Year annual % growth 1971 7.848517713397669 1972 1.4136895920119628 1973 9.899602032842196 1974 -6.853516099882853 1975 3.0019587027643126 1976 -18.364305519423112 1977 -14.80285219897894 1978 -13.461762003948792 1979 -2.8005658185393827 1980 43.69509941332632 1981 56.94513967249975 1982 49.267531160558974 1983 -15.412621112909491 1984 -3.113746928268853 1985 -20.378153578889467 1986 -23.524321625788986 1987 -16.55669159495082 1988 -34.72495161483218 1989 -25.979121043684003 1990 1.7641664824297436 1991 51.170367616931856 1992 3.770216691713003 1993 -30.063232785040412 1994 13.506836812555605 1995 -91.28017691482697 1996 30.835764314347614 1997 234.46006650718482 1998 62.50176121195946 1999 -21.459656953106148 2000 -95.58755668626092 2001 1432.8926702874817 2002 37.396390940698524 2003 91.22797899059373 2004 -30.71372740769756 2005 36.53317365903524 2006 24.359171332559157 2007 5.534897521427354 2008 18.074914748262216 2009 20.956618276477172 2010 32.603670578280486 2011 -28.561480659588938 2012 61.653193508505495 2013 23.601745780981403 2014 10.264481591344165 2015 -17.80995824731916 2016 -21.9890282985897 2017 -32.09840970518266 2018 10.492298957430052 2019 -14.132027457853766 2020 -20.256551968823345 2021 32.559928628515564