| 年度 | 实际值 |
|---|---|
| 1992 | 3.3 |
| 1993 | |
| 1994 | |
| 1995 | 3.4 |
| 1996 | |
| 1997 | |
| 1998 | |
| 1999 | 4.4464 |
| 2000 | 4.5797 |
| 2001 | 4.7393 |
| 2002 | 4.9378 |
| 2003 | 5.7917 |
| 2004 | 6.6182 |
| 2005 | 6.9534 |
| 2006 | 6.8263 |
| 2007 | 7.5702 |
| 2008 | 7.852 |
| 2009 | 8.0809 |
| 2010 | 7.8197 |
| 2011 | 9.2524 |
| 2012 | 9.5981 |
| 2013 | 9.3971 |
| 2014 | 8.7277 |
| 2015 | 8.2412 |