| 年度 | 实际值 |
|---|---|
| 1992 | 12.6 |
| 1993 | 7.8 |
| 1994 | |
| 1995 | 5.17 |
| 1996 | 5.04 |
| 1997 | 4.58 |
| 1998 | 2.24 |
| 1999 | 4.8 |
| 2000 | 3.04 |
| 2001 | 6.3 |
| 2002 | 7.14 |
| 2003 | 6.72 |
| 2004 | 6.1 |
| 2005 | 10.74 |
| 2006 | 13.38 |
| 2007 | 12.59 |
| 2008 | 7.3 |
| 2009 | |
| 2010 | 6.92 |
| 2011 | 1.8 |
| 2012 | 1.4 |
| 2013 | 1.4 |
| 2014 | -2.9 |
| 2015 | 4.28 |
| 2016 | 4.73 |
| 2017 | 5.58 |
| 2018 | 5.57 |