Year annual % 1961 2.59354341361398 1962 2.63402390540774 1963 2.68332707980713 1964 2.73394590266095 1965 2.7833399707246 1966 2.83371508534803 1967 2.87240807199467 1968 2.91551546033094 1969 2.9621576257799 1970 3.00020177514605 1971 3.04343179310279 1972 3.08457428598645 1973 3.10198424496887 1974 3.09829370593342 1975 2.78657684536874 1976 2.46083279937368 1977 2.41813965975759 1978 2.37609733976875 1979 2.32010802858839 1980 2.26897335528598 1981 2.23178324245008 1982 2.17312144774999 1983 2.08197793988306 1984 2.52381496535455 1985 2.9929202774016 1986 2.97618241720109 1987 2.95794132951344 1988 2.91250418130539 1989 2.88005965452853 1990 2.81691162830882 1991 2.779776802472 1992 2.74597223403598 1993 2.86268606275743 1994 2.8520446261962 1995 2.70139713559943 1996 2.67284423332925 1997 2.05368351414271 1998 2.13796271463219 1999 2.67047567259907 2000 3.81697887153797 2001 3.75963307173171 2002 2.34039442531377 2003 2.76801614231128 2004 3.39770601248237 2005 3.59877196603076 2006 3.75360549915507 2007 3.68155876257458 2008 3.3131079690881 2009 4.01710592389119 2010 4.15589722236467 2011 3.24414124523082 2012 2.77600777570712 2013 2.40667969204573 2014 2.39028820797079 2015 2.38840507871515 2016 2.38886575467523 2017 2.3910852337636 2018 2.39418462530963 2019 2.355238072353 2020 2.33208625068898 2021 2.31648825280279 2022 2.28055584966535 2023 2.25962565586274