| 年度 | 实际值 |
|---|---|
| 1992 | 9.8 |
| 1993 | 9.4 |
| 1994 | |
| 1995 | 10.23 |
| 1996 | 10.07 |
| 1997 | 9.63 |
| 1998 | 4.89 |
| 1999 | 6.95 |
| 2000 | 8.83 |
| 2001 | 6.08 |
| 2002 | 6.45 |
| 2003 | 9.68 |
| 2004 | 7.04 |
| 2005 | 13.29 |
| 2006 | 9.53 |
| 2007 | 7.05 |
| 2008 | 19.04 |
| 2009 | |
| 2010 | 23.06 |
| 2011 | 16.6 |
| 2012 | -2.5 |
| 2013 | 13 |
| 2014 | 14.5 |
| 2015 | 16.44 |
| 2016 | 24.01 |
| 2017 | 8.28 |
| 2018 | 9.65 |