| 年度 | 实际值 |
|---|---|
| 1992 | 6.5 |
| 1993 | 5.9 |
| 1994 | |
| 1995 | 6.14 |
| 1996 | 4.93 |
| 1997 | 5.14 |
| 1998 | 5.91 |
| 1999 | 3.69 |
| 2000 | 7.51 |
| 2001 | 3.77 |
| 2002 | 2.98 |
| 2003 | 1.49 |
| 2004 | 2.1 |
| 2005 | .6 |
| 2006 | |
| 2007 | -.44 |
| 2008 | -.47 |
| 2009 | |
| 2010 | -2.53 |
| 2011 | -2.3 |
| 2012 | -2.4 |
| 2013 | -4.1 |
| 2014 | -3.7 |
| 2015 | -5.44 |
| 2016 | -3.52 |
| 2017 | -8.94 |
| 2018 | -4.67 |