| 年度 | 实际值 |
|---|---|
| 1993 | 11 |
| 1994 | |
| 1995 | 2.1 |
| 1996 | 19.9 |
| 1997 | 20.4 |
| 1998 | 24.5 |
| 1999 | 24.7 |
| 2000 | 22 |
| 2001 | 1.65333333333333 |
| 2002 | |
| 2003 | 28.59 |
| 2004 | 36.17 |
| 2005 | 38 |
| 2006 | 39.54 |
| 2007 | 42.44 |
| 2008 | 44.63 |
| 2009 | |
| 2010 | 44.43 |
| 2011 | 48.19 |
| 2012 | 48.36 |
| 2013 | 48.32 |
| 2014 | 48.4 |
| 2015 | 48.28 |
| 2016 | 48.35 |
| 2017 | 46.29 |
| 2018 | 46.36 |