| 年度 | 实际值 |
|---|---|
| 1993 | 30.2 |
| 1994 | |
| 1995 | 36 |
| 1996 | 36.3 |
| 1997 | 40.8 |
| 1998 | 44.1 |
| 1999 | 44.8 |
| 2000 | 42.3 |
| 2001 | 2.53333333333333 |
| 2002 | |
| 2003 | 40.9 |
| 2004 | 40.21 |
| 2005 | 38 |
| 2006 | 44.34 |
| 2007 | 37.37 |
| 2008 | 37.15 |
| 2009 | |
| 2010 | 47.68 |
| 2011 | 51.59 |
| 2012 | 51.92 |
| 2013 | 51.11 |
| 2014 | 60.41 |
| 2015 | |
| 2016 | 61.58 |
| 2017 | 48.42 |
| 2018 | 48.44 |