Year annual % 1961 4.405074180164503 1962 4.404484356871216 1963 5.344165467203779 1964 8.916539849959118 1965 8.839041944902146 1966 8.769836950095131 1967 8.74553809975374 1968 8.740772430830699 1969 8.667882633266096 1970 8.617478591263637 1971 8.55964398250466 1972 8.519379227184963 1973 8.01414681044008 1974 6.120610776463286 1975 6.104051495292719 1976 6.142389273541993 1977 6.1749887810163475 1978 6.202810889411532 1979 6.234407596202035 1980 6.275768482890473 1981 6.240607164010043 1982 6.252858362336995 1983 6.419266492384305 1984 6.779820736641641 1985 6.82124958843455 1986 6.857079222958459 1987 6.877193827341409 1988 6.897313270505564 1989 6.8872922594631705 1990 6.883772904312535 1991 6.867393577621779 1992 6.723935654739495 1993 6.183121831463849 1994 5.2734872231930545 1995 5.037490152699626 1996 4.9738959894440535 1997 4.92887817962702 1998 4.90998403681353 1999 4.8727648016228695 2000 4.809358171700598 2001 4.750765999408289 2002 4.694725696106854 2003 4.591574465144912 2004 4.332180681126844 2005 4.359495256789058 2006 4.416585106587202 2007 4.4577894431675595 2008 4.460730685072789 2009 4.443951552033532 2010 4.412243420847514 2011 4.38583159000324 2012 4.365139469554459 2013 4.2954946573829975 2014 4.191405720230415 2015 4.075764597177745 2016 3.962237171257426 2017 3.853630488461453 2018 3.742600951095837 2019 3.655721231651833 2020 3.6078858888448098 2021 3.5462481657610923 2022 3.4636847955036023 2023 3.4184969179557196