| 年度 | 实际值 |
|---|---|
| 1995 | 51.9 |
| 1996 | 56.6 |
| 1997 | 56.49 |
| 1998 | 56.8 |
| 1999 | 57.8 |
| 2000 | 59.6 |
| 2001 | 61.52 |
| 2002 | 62.03 |
| 2003 | 62.24 |
| 2004 | 60.52 |
| 2005 | 61.27 |
| 2006 | 64.23 |
| 2007 | 62.13 |
| 2008 | 60.84 |
| 2009 | |
| 2010 | 59.43 |
| 2011 | 61.19 |
| 2012 | 60.71 |
| 2013 | 59.87 |
| 2014 | 64.65 |
| 2015 | 54.71 |
| 2016 | 55.36 |
| 2017 | 58.37 |
| 2018 | 60.17 |