| 年度 | 实际值 |
|---|---|
| 1993 | 18.2 |
| 1994 | |
| 1995 | 10.2 |
| 1996 | 10.7 |
| 1997 | .3 |
| 1998 | 9.1 |
| 1999 | 11.5 |
| 2000 | 8.3 |
| 2001 | 1.99333333333333 |
| 2002 | |
| 2003 | 19.75 |
| 2004 | 20.11 |
| 2005 | 33 |
| 2006 | 34.43 |
| 2007 | 32.22 |
| 2008 | 35.64 |
| 2009 | |
| 2010 | 40.25 |
| 2011 | 32.76 |
| 2012 | 34.62 |
| 2013 | 28.06 |
| 2014 | 6.75 |
| 2015 | 6.77 |
| 2016 | 32.57 |
| 2017 | 19.06 |
| 2018 | 40.72 |