Year annual % 1961 2.17386810638959 1962 2.2728918533378 1963 2.318877937557 1964 2.42704511869551 1965 2.41819321989917 1966 2.44025243751488 1967 2.65474678477131 1968 2.75613980522855 1969 2.69680372313037 1970 2.55014179388971 1971 2.00917428416867 1972 1.64096791210891 1973 1.71339519301278 1974 1.72429587876977 1975 1.71678036223655 1976 1.66218355569908 1977 1.63920737643257 1978 1.67476002377471 1979 1.68374146280831 1980 1.5599179649036 1981 1.36251089910957 1982 1.34419580522923 1983 1.41468036490133 1984 1.39116107330013 1985 1.37207302387443 1986 1.38664538284893 1987 1.40036291435214 1988 1.44903951995967 1989 1.4671405771336 1990 1.42854570393901 1991 1.39128476210504 1992 1.40600454010142 1993 1.44650383461611 1994 1.43901654513085 1995 1.44450397956995 1996 1.4367001101544 1997 1.37229402493903 1998 1.3133397029292 1999 1.31164599373427 2000 1.25228247927372 2001 1.05419487775652 2002 0.945302183064675 2003 0.907042396715275 2004 0.878482955573281 2005 0.879502933541775 2006 0.823120977302667 2007 0.745302497633524 2008 0.711545007164178 2009 0.771009503458442 2010 0.701110398374398 2011 0.729393790471232 2012 0.869403225669288 2013 0.821163785495365 2014 0.784827172615701 2015 0.695762433860479 2016 0.677661202777028 2017 0.741744903878247 2018 0.767717718370254 2019 0.78525898208049 2020 0.709498302393315 2021 0.727556393997221 2022 0.735015942105173 2023 0.651369032629572