Year annual % 1961 1.77712462109052 1962 1.53703684221733 1963 1.61021945224957 1964 1.73636319617259 1965 1.64624302502042 1966 1.8575152756726 1967 2.22447741197887 1968 2.25292406885326 1969 2.24910987984231 1970 2.23485514176548 1971 2.25304380675294 1972 2.30817098718581 1973 2.37278240368425 1974 2.45257536458332 1975 3.69939562776839 1976 4.81594373956117 1977 3.76843461238997 1978 2.86760142486727 1979 2.98537020862928 1980 3.10213696205313 1981 3.21354609915972 1982 3.2974527326651 1983 3.35320501916948 1984 3.38194161321637 1985 3.39768753510501 1986 3.33093272372226 1987 3.02828554053134 1988 2.74710605415951 1989 2.63176506303593 1990 2.4940676377263 1991 2.3846528039865 1992 2.32375186283265 1993 2.24036926865414 1994 2.10774651269655 1995 1.91804419938335 1996 1.76331956063309 1997 1.68115971162844 1998 1.51057323725397 1999 1.39842912410864 2000 1.40229085828763 2001 1.37593080261361 2002 1.34886695233422 2003 1.35423891111813 2004 1.40727321515229 2005 1.36408196251206 2006 1.44113729642515 2007 1.62790867702938 2008 1.70897167476718 2009 1.79590393152832 2010 1.85870199052442 2011 1.89839428094337 2012 1.94310213435967 2013 1.9667158178046 2014 1.97904881035906 2015 1.99994605069585 2016 1.99343168879913 2017 1.95700247075081 2018 1.9033254281097 2019 1.83944488568624 2020 1.73245672803153 2021 1.65770320084269 2022 1.62833925417918 2023 1.55401932380535