Year | Value | 2021 | 39.578144458281 | 2020 | 40.12297633873 | 2019 | 39.604088833541 | 2018 | 40.421336654213 | 2017 | 40.486197592362 | 2016 | 40.200809464508 | 2015 | 39.435450394354 | 2014 | 39.487339144873 | 2013 | 39.526255707763 | 2012 | 39.227895392279 | 2011 | 39.046284765463 | 2010 | 38.125259443753 | 2009 | 38.164176006642 | 2008 | 38.216064757161 | 2007 | 39.150062266501 | 2006 | 39.331672893317 | 2005 | 39.137090078871 | 2004 | 39.318700705687 | 2003 | 40.460253217102 | 2002 | 40.499169779992 | 2001 | 40.60294728103 | 2000 | 40.265670402657 | 1999 | 40.356475716065 | 1998 | 40.369447903694 | 1997 | 40.265670402657 | 1996 | 39.6300332088 | 1995 | 39.513283520133 | 1994 | 39.240867579909 | 1993 | 39.214923204649 | 1992 | 38.812785388128 | 1991 | 38.670091324201 | 1990 | 38.592258198423 | 1989 | 39.448422581984 | 1988 | 38.812785388128 | 1987 | 40.538086342881 | 1986 | 39.098173515982 | 1985 | 41.134806973848 | 1984 | 41.653694479037 | 1983 | 40.265670402657 | 1982 | 42.989829804898 | 1981 | 40.421336654213 | 1980 | 41.653694479037 | 1979 | 40.278642590286 | 1978 | 40.408364466584 | 1977 | 39.746782897468 | 1976 | 39.513283520133 | 1975 | 39.954337899543 | 1974 | 39.604088833541 | 1973 | 40.486197592362 | 1972 | 39.357617268576 | 1971 | 39.331672893317 | 1970 | 39.824616023246 | 1969 | 39.617061021171 | 1968 | 41.52397260274 | 1967 | 41.913138231631 | 1966 | 41.848277293483 | 1965 | 41.614777916148 | 1964 | 40.473225404732 | 1963 | 39.863532586135 | 1962 | 39.811643835616 | 1961 | 39.668949771689 |
|