| 年度 | 实际值 |
|---|---|
| 1995 | 44.7 |
| 1996 | 43.6 |
| 1997 | 14.04 |
| 1998 | 44.9 |
| 1999 | 44.3 |
| 2000 | 46.6 |
| 2001 | 47.43 |
| 2002 | 37.11 |
| 2003 | 40.42 |
| 2004 | 41 |
| 2005 | 33.39 |
| 2006 | 32.82 |
| 2007 | 32.98 |
| 2008 | 35.37 |
| 2009 | |
| 2010 | 41.33 |
| 2011 | 44.43 |
| 2012 | 44.07 |
| 2013 | 43.67 |
| 2014 | 43.98 |
| 2015 | 42.21 |
| 2016 | 39.97 |
| 2017 | 39.58 |
| 2018 | 38.43 |