| 年度 | 实际值 |
|---|---|
| 1995 | 64.4 |
| 1996 | 63.7 |
| 1997 | 73.05 |
| 1998 | 59.2 |
| 1999 | 57 |
| 2000 | 57.1 |
| 2001 | 57.42 |
| 2002 | 57.15 |
| 2003 | 58.39 |
| 2004 | 59.15 |
| 2005 | 63.44 |
| 2006 | 62.78 |
| 2007 | 62.93 |
| 2008 | 65.32 |
| 2009 | |
| 2010 | 71.21 |
| 2011 | 72.99 |
| 2012 | 73.28 |
| 2013 | 73.63 |
| 2014 | 67.6 |
| 2015 | 64.06 |
| 2016 | 63.34 |
| 2017 | 61.3 |
| 2018 | 57.75 |