| 年份 | 日本 |
|---|---|
| 2023 | - |
| 2022 | 6.17735 |
| 2021 | 6.09893 |
| 2020 | 6.06452 |
| 2019 | 5.91863 |
| 2018 | 5.82495 |
| 2017 | 5.75479 |
| 2016 | 5.71481 |
| 2015 | 5.74035 |
| 2014 | 5.7897 |
| 2013 | 5.85282 |
| 2012 | 6.00176 |
| 2011 | 6.23866 |
| 2010 | 6.52668 |
| 2009 | 6.96999 |
| 2008 | 7.53698 |
| 2007 | 8.02968 |
| 2006 | 8.16532 |
| 2005 | 7.89526 |
| 2004 | 7.48463 |
| 2003 | 7.07101 |
| 2002 | 6.72151 |
| 2001 | 6.67372 |
| 2000 | 6.88902 |
| 1999 | 6.92848 |
| 1998 | 6.75265 |
| 1997 | 6.57179 |
| 1996 | 6.42018 |
| 1995 | 6.32476 |
| 1994 | 6.3423 |
| 1993 | 6.41224 |
| 1992 | 6.4304 |
| 1991 | 6.38417 |
| 1990 | 6.30075 |
| 1989 | 6.21627 |
| 1988 | 6.13506 |
| 1987 | 6.04439 |
| 1986 | 5.95863 |
| 1985 | 5.88394 |
| 1984 | 5.79773 |
| 1983 | 5.68976 |
| 1982 | 5.5672 |
| 1981 | 5.41707 |
| 1980 | 5.27336 |
| 1979 | 5.12064 |
| 1978 | 4.93814 |
| 1977 | 4.78246 |
| 1976 | 4.67494 |
| 1975 | 4.57658 |
| 1974 | 4.52971 |
| 1973 | 4.55484 |
| 1972 | 4.57869 |
| 1971 | 4.58064 |
| 1970 | 4.55802 |
| 1969 | 4.52398 |
| 1968 | 4.47951 |
| 1967 | 4.41751 |
| 1966 | 4.296 |
| 1965 | 4.15179 |
| 1964 | 4.02272 |
| 1963 | 3.90959 |
| 1962 | 3.83826 |
| 1961 | 3.82818 |
| 1960 | 3.84611 |