| 年度 | 实际值 |
|---|---|
| 1995 | 37.7 |
| 1996 | 41 |
| 1997 | 46.43 |
| 1998 | 43.9 |
| 1999 | 43.9 |
| 2000 | 43.1 |
| 2001 | 43.81 |
| 2002 | 45.31 |
| 2003 | 45.26 |
| 2004 | 45.96 |
| 2005 | 41.62 |
| 2006 | 44.51 |
| 2007 | 43 |
| 2008 | 46.02 |
| 2009 | |
| 2010 | 43.38 |
| 2011 | 44.55 |
| 2012 | 44.45 |
| 2013 | 45.41 |
| 2014 | 43.89 |
| 2015 | 43.95 |
| 2016 | 43.12 |
| 2017 | 43.92 |
| 2018 | 43.15 |