| 年度 | 实际值 |
|---|---|
| 1993 | 31.9 |
| 1994 | |
| 1995 | 36.3 |
| 1996 | 35.9 |
| 1997 | 35.1 |
| 1998 | 31.9 |
| 1999 | 30.5 |
| 2000 | 31.9 |
| 2001 | 1.88 |
| 2002 | |
| 2003 | 32.23 |
| 2004 | 34.7 |
| 2005 | 44 |
| 2006 | 45.88 |
| 2007 | 46.84 |
| 2008 | 22.06 |
| 2009 | |
| 2010 | 45.75 |
| 2011 | 40.42 |
| 2012 | 40.73 |
| 2013 | 40.73 |
| 2014 | 41.17 |
| 2015 | 41.8 |
| 2016 | 41.73 |
| 2017 | 42.01 |
| 2018 | 43.73 |