| 年份 | 汤加 |
|---|---|
| 2023 | - |
| 2022 | 1.52103 |
| 2021 | 1.51183 |
| 2020 | 1.4851 |
| 2019 | 1.45308 |
| 2018 | 1.42691 |
| 2017 | 1.40574 |
| 2016 | 1.38529 |
| 2015 | 1.36072 |
| 2014 | 1.33998 |
| 2013 | 1.31914 |
| 2012 | 1.29526 |
| 2011 | 1.2535 |
| 2010 | 1.22014 |
| 2009 | 1.21202 |
| 2008 | 1.20689 |
| 2007 | 1.19807 |
| 2006 | 1.17884 |
| 2005 | 1.14871 |
| 2004 | 1.11481 |
| 2003 | 1.08856 |
| 2002 | 1.06963 |
| 2001 | 1.05056 |
| 2000 | 1.03349 |
| 1999 | 1.01231 |
| 1998 | 0.991033 |
| 1997 | 0.972082 |
| 1996 | 0.950194 |
| 1995 | 0.933352 |
| 1994 | 0.910602 |
| 1993 | 0.88144 |
| 1992 | 0.85089 |
| 1991 | 0.820394 |
| 1990 | 0.800369 |
| 1989 | 0.797333 |
| 1988 | 0.813789 |
| 1987 | 0.843851 |
| 1986 | 0.852137 |
| 1985 | 0.827473 |
| 1984 | 0.794497 |
| 1983 | 0.755259 |
| 1982 | 0.715928 |
| 1981 | 0.680809 |
| 1980 | 0.650043 |
| 1979 | 0.623749 |
| 1978 | 0.600936 |
| 1977 | 0.58175 |
| 1976 | 0.557657 |
| 1975 | 0.528944 |
| 1974 | 0.505 |
| 1973 | 0.493743 |
| 1972 | 0.491251 |
| 1971 | 0.48886 |
| 1970 | 0.492564 |
| 1969 | 0.497995 |
| 1968 | 0.50286 |
| 1967 | 0.509972 |
| 1966 | 0.51575 |
| 1965 | 0.518636 |
| 1964 | 0.527456 |
| 1963 | 0.537906 |
| 1962 | 0.551476 |
| 1961 | 0.574185 |
| 1960 | 0.59791 |