| 年度 | 实际值 |
|---|---|
| 1995 | 56.6 |
| 1996 | 55.7 |
| 1997 | 43.75 |
| 1998 | 49.3 |
| 1999 | 49 |
| 2000 | 48.9 |
| 2001 | 48.29 |
| 2002 | 48.13 |
| 2003 | 52.08 |
| 2004 | 52.8 |
| 2005 | 46.15 |
| 2006 | 44.48 |
| 2007 | 47.29 |
| 2008 | 49.29 |
| 2009 | |
| 2010 | 47.21 |
| 2011 | 56.35 |
| 2012 | 52.83 |
| 2013 | 50.29 |
| 2014 | 45.72 |
| 2015 | 45.22 |
| 2016 | 44.84 |
| 2017 | |
| 2018 | 42.19 |