| 年度 | 实际值 |
|---|---|
| 1995 | 46.9 |
| 1996 | 52.3 |
| 1997 | 55.45 |
| 1998 | 47.9 |
| 1999 | 37.8 |
| 2000 | 46.6 |
| 2001 | 48.38 |
| 2002 | 49.77 |
| 2003 | 52.23 |
| 2004 | 53.56 |
| 2005 | 59.98 |
| 2006 | 60.36 |
| 2007 | 60.09 |
| 2008 | 60.93 |
| 2009 | |
| 2010 | 60.56 |
| 2011 | 58.72 |
| 2012 | 57.84 |
| 2013 | 55.99 |
| 2014 | 48.89 |
| 2015 | 47.78 |
| 2016 | 45.78 |
| 2017 | 49.48 |
| 2018 | 49.22 |