| 序号 |
时间(年) |
数据(单位：-) |
| 1 |
2024 |
|
| 2 |
2023 |
|
| 3 |
2022 |
|
| 4 |
2021 |
|
| 5 |
2020 |
|
| 6 |
2019 |
|
| 7 |
2018 |
31.84 |
| 8 |
2017 |
31.67 |
| 9 |
2016 |
31.54 |
| 10 |
2015 |
31.29 |
| 11 |
2014 |
30.83 |
| 12 |
2013 |
30.23 |
| 13 |
2012 |
29.54 |
| 14 |
2011 |
28.80 |
| 15 |
2010 |
28.07 |
| 16 |
2009 |
27.42 |
| 17 |
2008 |
26.89 |
| 18 |
2007 |
26.55 |
| 19 |
2006 |
26.44 |
| 20 |
2005 |
26.45 |
| 21 |
2004 |
26.44 |
| 22 |
2003 |
26.44 |
| 23 |
2002 |
26.54 |
| 24 |
2001 |
26.69 |
| 25 |
2000 |
26.85 |
| 26 |
1999 |
27.03 |
| 27 |
1998 |
27.20 |
| 28 |
1997 |
27.32 |
| 29 |
1996 |
27.38 |
| 30 |
1995 |
27.42 |
| 31 |
1994 |
27.49 |
| 32 |
1993 |
27.59 |
| 33 |
1992 |
27.65 |
| 34 |
1991 |
27.66 |
| 35 |
1990 |
27.66 |
| 36 |
1989 |
27.64 |
| 37 |
1988 |
27.58 |
| 38 |
1987 |
27.44 |
| 39 |
1986 |
27.16 |
| 40 |
1985 |
26.68 |
| 41 |
1984 |
26.28 |
| 42 |
1983 |
26.06 |
| 43 |
1982 |
25.83 |
| 44 |
1981 |
25.61 |
| 45 |
1980 |
25.41 |
| 46 |
1979 |
25.16 |
| 47 |
1978 |
24.82 |
| 48 |
1977 |
24.41 |
| 49 |
1976 |
23.98 |
| 50 |
1975 |
23.54 |
| 51 |
1974 |
23.02 |
| 52 |
1973 |
22.44 |
| 53 |
1972 |
21.86 |
| 54 |
1971 |
21.32 |
| 55 |
1970 |
20.88 |
| 56 |
1969 |
20.54 |
| 57 |
1968 |
20.21 |
| 58 |
1967 |
19.81 |
| 59 |
1966 |
19.41 |
| 60 |
1965 |
19.08 |
| 61 |
1964 |
18.80 |
| 62 |
1963 |
18.54 |
| 63 |
1962 |
18.29 |
| 64 |
1961 |
18.07 |
| 65 |
1960 |
17.85 |
