| 年度 | 实际值 |
|---|---|
| 1995 | 65.3 |
| 1996 | 63.1 |
| 1997 | 6.26 |
| 1998 | 61.7 |
| 1999 | 56.9 |
| 2000 | 58.7 |
| 2001 | 56.8 |
| 2002 | 57.42 |
| 2003 | 58.63 |
| 2004 | 61.62 |
| 2005 | 56.16 |
| 2006 | 56.2 |
| 2007 | 57.06 |
| 2008 | 65.45 |
| 2009 | |
| 2010 | 66.7 |
| 2011 | 66.61 |
| 2012 | 61.05 |
| 2013 | 50.45 |
| 2014 | 44.26 |
| 2015 | 41.36 |
| 2016 | 41.29 |
| 2017 | 41.54 |
| 2018 | 44.01 |