| 年度 | 实际值 |
|---|---|
| 1995 | 39 |
| 1996 | 41.6 |
| 1997 | 36.02 |
| 1998 | 47.8 |
| 1999 | 48.2 |
| 2000 | 48.6 |
| 2001 | 42.96 |
| 2002 | 38.94 |
| 2003 | 37.93 |
| 2004 | 37.82 |
| 2005 | 47.96 |
| 2006 | 41.38 |
| 2007 | 41.62 |
| 2008 | 39.33 |
| 2009 | |
| 2010 | 44.45 |
| 2011 | 43.78 |
| 2012 | 44.85 |
| 2013 | 44.95 |
| 2014 | 44.4 |
| 2015 | 43.32 |
| 2016 | 44.51 |
| 2017 | 44.55 |
| 2018 | 46.21 |