| 年度 | 实际值 |
|---|---|
| 1995 | 44.7 |
| 1996 | 41.6 |
| 1997 | 55.04 |
| 1998 | 35.6 |
| 1999 | 37.3 |
| 2000 | 39.4 |
| 2001 | 43.15 |
| 2002 | 44.42 |
| 2003 | 47.69 |
| 2004 | 47.32 |
| 2005 | 46.13 |
| 2006 | 47 |
| 2007 | 47.21 |
| 2008 | 47.61 |
| 2009 | |
| 2010 | 49.15 |
| 2011 | 49.2 |
| 2012 | 47.69 |
| 2013 | 47.13 |
| 2014 | 47.73 |
| 2015 | 45.99 |
| 2016 | 45.38 |
| 2017 | 44.66 |
| 2018 | 41.12 |