| 年度 | 实际值 |
|---|---|
| 1993 | 24.3 |
| 1994 | |
| 1995 | 27.5 |
| 1996 | 47 |
| 1997 | 54.8 |
| 1998 | 55.3 |
| 1999 | 56.2 |
| 2000 | 54.7 |
| 2001 | 3.53333333333333 |
| 2002 | |
| 2003 | 52.59 |
| 2004 | 52.59 |
| 2005 | 48 |
| 2006 | 48.06 |
| 2007 | 69.61 |
| 2008 | 26.29 |
| 2009 | |
| 2010 | 30.25 |
| 2011 | 38.14 |
| 2012 | 37.82 |
| 2013 | 39.07 |
| 2014 | 39.96 |
| 2015 | 40.55 |
| 2016 | 40.43 |
| 2017 | 40.7 |
| 2018 | 40.56 |