| 年度 | 实际值 |
|---|---|
| 1993 | 9.3 |
| 1994 | |
| 1995 | 7.6 |
| 1996 | 8.2 |
| 1997 | 8.2 |
| 1998 | 23.5 |
| 1999 | 27.5 |
| 2000 | 27.9 |
| 2001 | 1.66666666666667 |
| 2002 | |
| 2003 | 27.33 |
| 2004 | 27.5 |
| 2005 | 40 |
| 2006 | 38.4 |
| 2007 | 38.4 |
| 2008 | 35.93 |
| 2009 | |
| 2010 | 39.23 |
| 2011 | 43.43 |
| 2012 | 42.84 |
| 2013 | 33.71 |
| 2014 | 42.34 |
| 2015 | 42.51 |
| 2016 | 42.57 |
| 2017 | 41.3 |
| 2018 | 41.3 |