| 年度 | 实际值 |
|---|---|
| 1992 | 1.6 |
| 1993 | |
| 1994 | |
| 1995 | 1.6 |
| 1996 | |
| 1997 | |
| 1998 | |
| 1999 | 1.4051 |
| 2000 | 1.368 |
| 2001 | 1.5125 |
| 2002 | 1.4563 |
| 2003 | 1.5741 |
| 2004 | 1.5074 |
| 2005 | 1.5122 |
| 2006 | 1.1725 |
| 2007 | 1.2534 |
| 2008 | 1.54 |
| 2009 | 1.5479 |
| 2010 | 1.5419 |
| 2011 | 1.5773 |
| 2012 | 1.7413 |
| 2013 | 1.7779 |
| 2014 | 1.7935 |
| 2015 | 1.8121 |