| 年度 | 数值 | 单位 | 发布日期 |
| 1998/1999 | 1.16 | 吨/公顷 | 2026-9 |
| 1997/1998 | 1.714 | 吨/公顷 | 2026-9 |
| 1996/1997 | 1 | 吨/公顷 | 2026-9 |
| 1995/1996 | 0.5 | 吨/公顷 | 2026-9 |
| 1994/1995 | 0.5 | 吨/公顷 | 2026-9 |
| 1993/1994 | 0.5 | 吨/公顷 | 2026-9 |
| 1992/1993 | 0.5 | 吨/公顷 | 2026-9 |
| 1991/1992 | 1 | 吨/公顷 | 2026-9 |
| 1990/1991 | 0.846 | 吨/公顷 | 2026-9 |
| 1989/1990 | 0.9 | 吨/公顷 | 2026-9 |
| 1988/1989 | 0.75 | 吨/公顷 | 2026-9 |
| 1987/1988 | 0.807 | 吨/公顷 | 2026-9 |
| 1986/1987 | 0.948 | 吨/公顷 | 2026-9 |
| 1985/1986 | 0.593 | 吨/公顷 | 2026-9 |
| 1984/1985 | 1.14 | 吨/公顷 | 2026-9 |
| 1983/1984 | 0.875 | 吨/公顷 | 2026-9 |
| 1982/1983 | 0.929 | 吨/公顷 | 2026-9 |
| 1981/1982 | 1.077 | 吨/公顷 | 2026-9 |
| 1980/1981 | 1.357 | 吨/公顷 | 2026-9 |
| 1979/1980 | 1.375 | 吨/公顷 | 2026-9 |
| 1978/1979 | 1.375 | 吨/公顷 | 2026-9 |
| 1977/1978 | 1.5 | 吨/公顷 | 2026-9 |
| 1976/1977 | 1.571 | 吨/公顷 | 2026-9 |
| 1975/1976 | 1.308 | 吨/公顷 | 2026-9 |
| 1974/1975 | 1.231 | 吨/公顷 | 2026-9 |
| 1973/1974 | 1.714 | 吨/公顷 | 2026-9 |
| 1972/1973 | 1.667 | 吨/公顷 | 2026-9 |
| 1971/1972 | 1.667 | 吨/公顷 | 2026-9 |
| 1970/1971 | 1.667 | 吨/公顷 | 2026-9 |
| 1969/1970 | 1.667 | 吨/公顷 | 2026-9 |
| 1968/1969 | 1.667 | 吨/公顷 | 2026-9 |
| 1967/1968 | 1.667 | 吨/公顷 | 2026-9 |
| 1966/1967 | 1.667 | 吨/公顷 | 2026-9 |
| 1965/1966 | 1 | 吨/公顷 | 2026-9 |
| 1964/1965 | 2 | 吨/公顷 | 2026-9 |