| 年度 | 实际值 |
|---|---|
| 1995 | 62.5 |
| 1996 | 61.7 |
| 1997 | 48.19 |
| 1998 | 64.1 |
| 1999 | 64.4 |
| 2000 | 62.2 |
| 2001 | 62.75 |
| 2002 | 62.59 |
| 2003 | 62.73 |
| 2004 | 62.94 |
| 2005 | 54.18 |
| 2006 | 55.08 |
| 2007 | 56.91 |
| 2008 | 57.16 |
| 2009 | |
| 2010 | 55.96 |
| 2011 | 58.7 |
| 2012 | 60.17 |
| 2013 | 64.6 |
| 2014 | 64.13 |
| 2015 | 63.32 |
| 2016 | 61.73 |
| 2017 | 59.77 |
| 2018 | 57.56 |