| 序号 |
时间(年) |
数据(单位：-) |
| 1 |
2021 |
|
| 2 |
2020 |
|
| 3 |
2019 |
|
| 4 |
2018 |
|
| 5 |
2017 |
|
| 6 |
2016 |
|
| 7 |
2015 |
11.82 |
| 8 |
2014 |
11.51 |
| 9 |
2013 |
11.41 |
| 10 |
2012 |
11.76 |
| 11 |
2011 |
12.15 |
| 12 |
2010 |
11.08 |
| 13 |
2009 |
10.53 |
| 14 |
2008 |
10.16 |
| 15 |
2007 |
9.77 |
| 16 |
2006 |
9.66 |
| 17 |
2005 |
9.29 |
| 18 |
2004 |
13.97 |
| 19 |
2003 |
11.66 |
| 20 |
2002 |
11.90 |
| 21 |
2001 |
11.20 |
| 22 |
2000 |
9.82 |
| 23 |
1999 |
10.83 |
| 24 |
1998 |
9.56 |
| 25 |
1997 |
8.64 |
| 26 |
1996 |
7.95 |
| 27 |
1995 |
7.54 |
| 28 |
1994 |
6.93 |
| 29 |
1993 |
6.40 |
| 30 |
1992 |
5.90 |
| 31 |
1991 |
5.83 |
| 32 |
1990 |
5.94 |
| 33 |
1985 |
5.38 |
| 34 |
1980 |
4.62 |
| 35 |
1978 |
3.88 |
| 36 |
1975 |
2.94 |
| 37 |
1970 |
2.80 |
| 38 |
1965 |
4.20 |
| 39 |
1962 |
5.78 |
