Year | Value | 2021 | 61.91 | 2020 | 62.517 | 2019 | 63.051 | 2018 | 62.606 | 2017 | 62.288 | 2016 | 61.628 | 2015 | 61.126 | 2014 | 60.578 | 2013 | 59.995 | 2012 | 59.397 | 2011 | 58.675 | 2010 | 57.72 | 2009 | 56.765 | 2008 | 55.854 | 2007 | 54.863 | 2006 | 53.822 | 2005 | 52.728 | 2004 | 52.247 | 2003 | 51.649 | 2002 | 50.731 | 2001 | 50.448 | 2000 | 49.885 | 1999 | 48.107 | 1998 | 48.939 | 1997 | 48.54 | 1996 | 47.998 | 1995 | 47.212 | 1994 | 46.655 | 1993 | 46.113 | 1992 | 45.567 | 1991 | 44.456 | 1990 | 42.47 | 1989 | 43.068 | 1988 | 43.159 | 1987 | 43.639 | 1986 | 36.197 | 1985 | 35.69 | 1984 | 34.608 | 1983 | 34.227 | 1982 | 41.484 | 1981 | 41.391 | 1980 | 41 | 1979 | 40.519 | 1978 | 39.41 | 1977 | 39.443 | 1976 | 39.435 | 1975 | 37.236 | 1974 | 37.465 | 1973 | 39.524 | 1972 | 39.484 | 1971 | 40.736 | 1970 | 40.716 | 1969 | 40.639 | 1968 | 40.65 | 1967 | 40.499 | 1966 | 38.081 | 1965 | 40.224 | 1964 | 39.959 | 1963 | 39.709 | 1962 | 39.154 | 1961 | 38.732 | 1960 | 38.091 |
|