| 年度 | 实际值 |
|---|---|
| 1992 | 29.7 |
| 1993 | 30.18 |
| 1994 | 30.8 |
| 1995 | 31.46 |
| 1996 | 32.32 |
| 1997 | 33.14 |
| 1998 | 33.81 |
| 1999 | 34.71 |
| 2000 | 35.89 |
| 2001 | 91.34 |
| 2002 | 91.98 |
| 2003 | 92.18 |
| 2004 | 92.21 |
| 2005 | 92.16 |
| 2006 | 92.21 |
| 2007 | 92.25 |
| 2008 | 92.38 |
| 2009 | 92.7 |
| 2010 | 93.19 |
| 2011 | 93.57 |
| 2012 | 93.92 |
| 2013 | 94.57 |
| 2014 | 95.09 |
| 2015 | 96.1 |
| 2016 | 96.8477 |
| 2017 | 98 |
| 2018 | 99 |