Year annual % 1977 18.4568835098337 1978 18.1353767560665 1979 20.8828828828831 1980 21.821433894768 1981 18.7874709409026 1982 7.81274141216489 1983 6.09534728193344 1984 5.65961278703288 1985 2.50138492350979 1986 0.557079903550532 1987 -0.872333388457509 1988 4.00000000000013 1989 5.59294871794896 1990 2.72423736530525 1991 2.64460367880678 1992 3.77833753148618 1993 2.80859916782245 1994 3.77065767284965 1995 1.86882475298978 1996 2.03235172127782 1997 1.24452782989343 1998 1.37769330389496 1999 0.577427638677119 2000 2.18181818181821 2001 3.14099305202543 2002 1.06721547992874 2003 2.15492809908679 2004 2.3129167822611 2005 3.475806937554 2006 4.25195321977967 2007 3.85882922469653 2008 8.0332732765034 2009 -0.308654779585642 2010 3.43650905943351 2011 3.0334728033474 2012 2.41077704021862 2013 -0.0439997864828058 2014 -0.98360305555498 2015 -0.515448031435329 2016 1.65038994431573 2017 0.908458255874249 2018 0.804102313277033 2019 0.598149764736022 2020 -0.740732597045498 2021 1.21951193916838 2022 2.5805392590792 2023 2.69612269814564