| 年度 | 实际值 |
|---|---|
| 1995 | 86.2 |
| 1996 | 82.8 |
| 1997 | 82.99 |
| 1998 | 83.8 |
| 1999 | 84.1 |
| 2000 | 89.7 |
| 2001 | 88.69 |
| 2002 | 86.08 |
| 2003 | 85.33 |
| 2004 | 84.58 |
| 2005 | 85.92 |
| 2006 | 85.64 |
| 2007 | 84.97 |
| 2008 | 85.08 |
| 2009 | |
| 2010 | 82.24 |
| 2011 | 82.05 |
| 2012 | 80.88 |
| 2013 | 79.36 |
| 2014 | 75.53 |
| 2015 | 64.88 |
| 2016 | 56.07 |
| 2017 | |
| 2018 | 53.95 |