Year annual % 1971 1.09999999900012 1972 -0.0989119673600758 1973 2.47524752475231 1974 7.05314009565229 1975 2.2563176895509 1976 4.41306266552893 1977 4.90278951821559 1978 8.10126582278465 1979 7.02576112412187 1980 9.68271334792129 1981 19.1271820448877 1982 103.55871886121 1983 25.534759358289 1984 15.4009994265582 1985 11.5212607368495 1986 16.5499681731383 1987 26.3790278536323 1988 58.7208297320654 1989 244.550932984827 1990 567.878800666191 1991 76.7694992087347 1992 46.0985621037431 1993 36.9641666120718 1994 32.9912766093522 1995 27.951388563304 1996 19.7949669196707 1997 14.9131586149599 1998 11.5978554257235 1999 7.15407291179862 2000 9.90017538843064 2001 5.40833545566148 2002 1.90528215048055 2003 0.682701375787681 2004 3.38264681884691 2005 2.18379872390258 2006 1.28469394366408 2007 2.45874312385402 2008 4.16497193524764 2009 3.79539242483406 2010 2.58069370250543 2011 4.2394014962594 2012 3.56037151702783 2013 0.991982606332428 2014 0.0538213132399802 2015 -0.87412587412577 2016 -0.664767331433961 2017 2.0759355367385 2018 1.81295156542679 2019 2.227478809383 2020 3.37446972618589 2021 5.05502704719272 2022 14.4294507575758 2023 11.5289127961105