| 年份 | 日本 |
|---|---|
| 2023 | - |
| 2022 | 7.12902 |
| 2021 | 6.84978 |
| 2020 | 6.5648 |
| 2019 | 6.44301 |
| 2018 | 6.30765 |
| 2017 | 6.11224 |
| 2016 | 6.05272 |
| 2015 | 6.03689 |
| 2014 | 5.90673 |
| 2013 | 5.82657 |
| 2012 | 5.76867 |
| 2011 | 5.73844 |
| 2010 | 5.77299 |
| 2009 | 5.83231 |
| 2008 | 5.90556 |
| 2007 | 6.06657 |
| 2006 | 6.31717 |
| 2005 | 6.61784 |
| 2004 | 7.07628 |
| 2003 | 7.66101 |
| 2002 | 8.17102 |
| 2001 | 8.3203 |
| 2000 | 8.05994 |
| 1999 | 7.65395 |
| 1998 | 7.24159 |
| 1997 | 6.89381 |
| 1996 | 6.85114 |
| 1995 | 7.07372 |
| 1994 | 7.11523 |
| 1993 | 6.93872 |
| 1992 | 6.75848 |
| 1991 | 6.60893 |
| 1990 | 6.51722 |
| 1989 | 6.54216 |
| 1988 | 6.62292 |
| 1987 | 6.65331 |
| 1986 | 6.61881 |
| 1985 | 6.54854 |
| 1984 | 6.47863 |
| 1983 | 6.40927 |
| 1982 | 6.32621 |
| 1981 | 6.24568 |
| 1980 | 6.17645 |
| 1979 | 6.0961 |
| 1978 | 5.99673 |
| 1977 | 5.88704 |
| 1976 | 5.75172 |
| 1975 | 5.62358 |
| 1974 | 5.48501 |
| 1973 | 5.31402 |
| 1972 | 5.16761 |
| 1971 | 5.06822 |
| 1970 | 4.97511 |
| 1969 | 4.93286 |
| 1968 | 4.96566 |
| 1967 | 4.99783 |
| 1966 | 4.99662 |
| 1965 | 4.96816 |
| 1964 | 4.9357 |
| 1963 | 4.88817 |
| 1962 | 4.81653 |
| 1961 | 4.68645 |
| 1960 | 4.53068 |