| 年度 | 实际值 |
|---|---|
| 1992 | 5.6 |
| 1993 | 4.3 |
| 1994 | |
| 1995 | 3.07 |
| 1996 | 4.83 |
| 1997 | |
| 1998 | 5.62 |
| 1999 | 4.5 |
| 2000 | 3.72 |
| 2001 | 3.76 |
| 2002 | 4.53 |
| 2003 | 4.35 |
| 2004 | 4.52 |
| 2005 | 4.19 |
| 2006 | 7.33 |
| 2007 | 13.41 |
| 2008 | 11.28 |
| 2009 | |
| 2010 | 9.67 |
| 2011 | 6.6 |
| 2012 | -.7 |
| 2013 | 10 |
| 2014 | 9.2 |
| 2015 | 13.29 |
| 2016 | 10.84 |
| 2017 | 1.74 |
| 2018 | 6.57 |