| 年度 | 实际值 |
|---|---|
| 1993 | 30.3 |
| 1994 | |
| 1995 | 22 |
| 1996 | 22 |
| 1997 | 30.7 |
| 1998 | 36 |
| 1999 | 36.9 |
| 2000 | 39.5 |
| 2001 | 2.63333333333333 |
| 2002 | |
| 2003 | 40.31 |
| 2004 | 39.11 |
| 2005 | 41 |
| 2006 | 39.72 |
| 2007 | 38.85 |
| 2008 | 38.62 |
| 2009 | |
| 2010 | 40.97 |
| 2011 | 41.23 |
| 2012 | 41.3 |
| 2013 | 40.84 |
| 2014 | 39.93 |
| 2015 | 39.93 |
| 2016 | 40.1 |
| 2017 | 40.1 |
| 2018 | 40.1 |