| 年度 | 实际值 |
|---|---|
| 1995 | 57.3 |
| 1996 | 57.5 |
| 1997 | 42.03 |
| 1998 | 57.3 |
| 1999 | 55.7 |
| 2000 | 54.4 |
| 2001 | 56.36 |
| 2002 | 54.03 |
| 2003 | 57.75 |
| 2004 | 60.77 |
| 2005 | 62.04 |
| 2006 | 62.74 |
| 2007 | 63.11 |
| 2008 | 60.35 |
| 2009 | |
| 2010 | 57.29 |
| 2011 | 60.43 |
| 2012 | 57.47 |
| 2013 | 55.22 |
| 2014 | 50.4 |
| 2015 | 50.55 |
| 2016 | 45.18 |
| 2017 | 47.79 |
| 2018 | 49.52 |