| 年度 | 实际值 |
|---|---|
| 1992 | 5.3 |
| 1993 | 4.2 |
| 1994 | |
| 1995 | 2.14 |
| 1996 | 2.09 |
| 1997 | 3.28 |
| 1998 | 5.63 |
| 1999 | 4.3 |
| 2000 | 5.81 |
| 2001 | 5.26 |
| 2002 | 5.19 |
| 2003 | 1.65 |
| 2004 | 3.99 |
| 2005 | 4.62 |
| 2006 | 9.34 |
| 2007 | 8.5 |
| 2008 | 8.24 |
| 2009 | |
| 2010 | 8.07 |
| 2011 | 11 |
| 2012 | 1.2 |
| 2013 | 15.9 |
| 2014 | 11.1 |
| 2015 | 12.33 |
| 2016 | 12.02 |
| 2017 | -1.46 |
| 2018 | 7.74 |