| 年份 | 汤加 |
|---|---|
| 2023 | - |
| 2022 | 1.31736 |
| 2021 | 1.29252 |
| 2020 | 1.26689 |
| 2019 | 1.29635 |
| 2018 | 1.3467 |
| 2017 | 1.34823 |
| 2016 | 1.33538 |
| 2015 | 1.30434 |
| 2014 | 1.26127 |
| 2013 | 1.21723 |
| 2012 | 1.18048 |
| 2011 | 1.18532 |
| 2010 | 1.20045 |
| 2009 | 1.19601 |
| 2008 | 1.17663 |
| 2007 | 1.15528 |
| 2006 | 1.14921 |
| 2005 | 1.15544 |
| 2004 | 1.15348 |
| 2003 | 1.13526 |
| 2002 | 1.10682 |
| 2001 | 1.07124 |
| 2000 | 1.03151 |
| 1999 | 1.00632 |
| 1998 | 0.996054 |
| 1997 | 0.987255 |
| 1996 | 0.979665 |
| 1995 | 0.959816 |
| 1994 | 0.924878 |
| 1993 | 0.893696 |
| 1992 | 0.868276 |
| 1991 | 0.85112 |
| 1990 | 0.844492 |
| 1989 | 0.830255 |
| 1988 | 0.7952 |
| 1987 | 0.745246 |
| 1986 | 0.707336 |
| 1985 | 0.691821 |
| 1984 | 0.689958 |
| 1983 | 0.697645 |
| 1982 | 0.70858 |
| 1981 | 0.711324 |
| 1980 | 0.702806 |
| 1979 | 0.695761 |
| 1978 | 0.686024 |
| 1977 | 0.672648 |
| 1976 | 0.654923 |
| 1975 | 0.633196 |
| 1974 | 0.610905 |
| 1973 | 0.595663 |
| 1972 | 0.590191 |
| 1971 | 0.584761 |
| 1970 | 0.584176 |
| 1969 | 0.586446 |
| 1968 | 0.591818 |
| 1967 | 0.600858 |
| 1966 | 0.60494 |
| 1965 | 0.607508 |
| 1964 | 0.61741 |
| 1963 | 0.628957 |
| 1962 | 0.639309 |
| 1961 | 0.654098 |
| 1960 | 0.667894 |