| 年度 | 实际值 |
|---|---|
| 1995 | 68.4 |
| 1996 | 71.5 |
| 1997 | 28.47 |
| 1998 | 72.7 |
| 1999 | 72 |
| 2000 | 71.7 |
| 2001 | 69.88 |
| 2002 | 67.34 |
| 2003 | 57.63 |
| 2004 | 58.97 |
| 2005 | 64.75 |
| 2006 | 63.42 |
| 2007 | 64.96 |
| 2008 | 67.35 |
| 2009 | |
| 2010 | 68.57 |
| 2011 | 68.37 |
| 2012 | 68.54 |
| 2013 | 69.59 |
| 2014 | 74.85 |
| 2015 | 75.84 |
| 2016 | 76.35 |
| 2017 | 77.37 |
| 2018 | 77.54 |