Year annual % 1961 1.8870907128584 1962 2.03819990200126 1963 2.18351749145652 1964 2.31550617255799 1965 2.43607717525374 1966 2.54098408314936 1967 2.66778792625351 1968 2.75565466046345 1969 2.83058914324168 1970 2.90281974909526 1971 2.94223756636724 1972 2.99400217719842 1973 2.99100503428902 1974 3.00594151221225 1975 3.0675443304544 1976 2.84182748542272 1977 2.65548175657098 1978 1.70377521121895 1979 1.61226474644176 1980 1.930410097462 1981 1.16127103883721 1982 1.81909503749973 1983 2.70446507258018 1984 2.75997433504885 1985 2.90614919793084 1986 3.12256945652249 1987 3.26537163746685 1988 3.58337624484119 1989 6.42210939531102 1990 6.09436073046608 1991 3.34768971230455 1992 3.20257696605466 1993 3.24084628891261 1994 3.16913849081237 1995 2.96631636921689 1996 2.74610275033798 1997 2.58297473472435 1998 2.49115076791854 1999 2.40883758441721 2000 2.27194936669291 2001 2.02757940882814 2002 1.71558953640231 2003 1.41434290218581 2004 1.24422104996521 2005 1.20234000182313 2006 1.19983522844956 2007 1.2473242341721 2008 1.33630166361813 2009 1.4303035696071 2010 1.5047354003649 2011 1.56298266563295 2012 1.63406204857906 2013 1.69446732352455 2014 1.73094393878771 2015 1.75460038083267 2016 1.76502653275581 2017 1.75699918544662 2018 1.72516455160384 2019 1.68846817343864 2020 1.72031062423917 2021 1.63585889002733 2022 1.44635918427576 2023 1.4372197796667