| 年份 | 日本 |
|---|---|
| 2023 | - |
| 2022 | 6.54329 |
| 2021 | 6.75378 |
| 2020 | 6.98999 |
| 2019 | 7.25706 |
| 2018 | 7.54884 |
| 2017 | 7.79285 |
| 2016 | 7.93896 |
| 2015 | 7.97628 |
| 2014 | 7.8923 |
| 2013 | 7.719 |
| 2012 | 7.56484 |
| 2011 | 7.28741 |
| 2010 | 7.0057 |
| 2009 | 6.89551 |
| 2008 | 6.76918 |
| 2007 | 6.5814 |
| 2006 | 6.53705 |
| 2005 | 6.53168 |
| 2004 | 6.40229 |
| 2003 | 6.3249 |
| 2002 | 6.27163 |
| 2001 | 6.25156 |
| 2000 | 6.30211 |
| 1999 | 6.37671 |
| 1998 | 6.46586 |
| 1997 | 6.64838 |
| 1996 | 6.92186 |
| 1995 | 7.25372 |
| 1994 | 7.76628 |
| 1993 | 8.41288 |
| 1992 | 8.98004 |
| 1991 | 9.16477 |
| 1990 | 8.89156 |
| 1989 | 8.44508 |
| 1988 | 7.98789 |
| 1987 | 7.59037 |
| 1986 | 7.51642 |
| 1985 | 7.73907 |
| 1984 | 7.77886 |
| 1983 | 7.6006 |
| 1982 | 7.43888 |
| 1981 | 7.32157 |
| 1980 | 7.2631 |
| 1979 | 7.3209 |
| 1978 | 7.43782 |
| 1977 | 7.50237 |
| 1976 | 7.50355 |
| 1975 | 7.48291 |
| 1974 | 7.47376 |
| 1973 | 7.46088 |
| 1972 | 7.42408 |
| 1971 | 7.36948 |
| 1970 | 7.28337 |
| 1969 | 7.12771 |
| 1968 | 6.87592 |
| 1967 | 6.53525 |
| 1966 | 6.1164 |
| 1965 | 5.72074 |
| 1964 | 5.3941 |
| 1963 | 5.1341 |
| 1962 | 4.99299 |
| 1961 | 4.95993 |
| 1960 | 4.96228 |