| 年度 | 实际值 |
|---|---|
| 1993 | 25 |
| 1994 | |
| 1995 | 44.7 |
| 1996 | 42.7 |
| 1997 | 44.4 |
| 1998 | 45.4 |
| 1999 | 45.9 |
| 2000 | 46 |
| 2001 | 3.10666666666667 |
| 2002 | |
| 2003 | 46.81 |
| 2004 | 46.03 |
| 2005 | 46 |
| 2006 | 44.48 |
| 2007 | 44.77 |
| 2008 | 44.66 |
| 2009 | |
| 2010 | 44.78 |
| 2011 | 36.83 |
| 2012 | 39.49 |
| 2013 | 38.79 |
| 2014 | 37.81 |
| 2015 | 20.68 |
| 2016 | 21.04 |
| 2017 | 27.08 |
| 2018 | 27.6 |