| 年度 | 实际值 |
|---|---|
| 1995 | 46.9 |
| 1996 | 46.3 |
| 1997 | 47.89 |
| 1998 | 46.6 |
| 1999 | 47.6 |
| 2000 | 48.7 |
| 2001 | 49.29 |
| 2002 | 50.39 |
| 2003 | 52.64 |
| 2004 | 54.14 |
| 2005 | 51.79 |
| 2006 | 52.3 |
| 2007 | 51.59 |
| 2008 | 50.84 |
| 2009 | |
| 2010 | 48.69 |
| 2011 | 47.63 |
| 2012 | 46.59 |
| 2013 | 45.48 |
| 2014 | 44.76 |
| 2015 | 43.29 |
| 2016 | 41.56 |
| 2017 | |
| 2018 | 40.42 |