| 年度 | 实际值 |
|---|---|
| 1993 | 25.9 |
| 1994 | |
| 1995 | 9.1 |
| 1996 | 9.3 |
| 1997 | 27.5 |
| 1998 | 27.9 |
| 1999 | 28.1 |
| 2000 | 30.3 |
| 2001 | 1.99333333333333 |
| 2002 | |
| 2003 | 23.45 |
| 2004 | 23.53 |
| 2005 | 23 |
| 2006 | 24.38 |
| 2007 | 30.07 |
| 2008 | 31.76 |
| 2009 | |
| 2010 | 38 |
| 2011 | 38.18 |
| 2012 | 40.81 |
| 2013 | 41.5 |
| 2014 | 41.89 |
| 2015 | 41.75 |
| 2016 | 41.94 |
| 2017 | 45.87 |
| 2018 | 43.46 |