Year annual % 1961 0.911525536470683 1962 1.22493081884298 1963 1.03901066517559 1964 1.11990124963074 1965 1.1376686982108 1966 0.71987626682955 1967 0.328903404633494 1968 0.2549025372326 1969 0.490087859971103 1970 0.493889466721461 1971 0.953656918277231 1972 1.21304031189342 1973 1.10466656648279 1974 1.30405816817688 1975 1.09244783943894 1976 0.494942519180953 1977 0.173662846984142 1978 0.179439197124502 1979 0.234251269062172 1980 0.355980931791434 1981 0.294773135465379 1982 0.082107428492381 1983 0.0265336520751997 1984 0.1027856081308 1985 0.193256818675591 1986 0.44867099908019 1987 0.648083393492208 1988 0.725614578503426 1989 0.972627746123582 1990 1.25174570700817 1991 1.33968316953886 1992 1.32834757125223 1993 1.34238702924688 1994 1.36184013740089 1995 1.40474246355929 1996 1.36114394109864 1997 1.25350248369427 1998 1.24387080269218 1999 1.35062128530242 2000 1.34408299573143 2001 1.19045634528707 2002 1.04766081596443 2003 1.21520087964639 2004 1.42133256471314 2005 1.53005466340868 2006 1.59505191774492 2007 1.54438684650549 2008 1.78749663225793 2009 1.85177523043645 2010 1.8254058035237 2011 2.22266050326725 2012 2.40154189982875 2013 2.31117625275217 2014 2.35697870484045 2015 2.35995118136865 2016 2.15531198799205 2017 2.43097641776115 2018 1.92883751398765 2019 1.9628449198635 2020 1.66635867423273 2021 1.51834936706612 2022 2.01666790212729 2023 2.34600975458798