| 年度 | 实际值 |
|---|---|
| 1995 | 49.7 |
| 1996 | 51.5 |
| 1997 | 55.28 |
| 1998 | 47.6 |
| 1999 | 47.1 |
| 2000 | 45.4 |
| 2001 | 45.98 |
| 2002 | 46 |
| 2003 | 46.43 |
| 2004 | 46.86 |
| 2005 | 45.55 |
| 2006 | 47.33 |
| 2007 | 48.18 |
| 2008 | 48.07 |
| 2009 | |
| 2010 | 45.79 |
| 2011 | 44.48 |
| 2012 | 43.66 |
| 2013 | 43.55 |
| 2014 | 39.67 |
| 2015 | 37.93 |
| 2016 | 36.8 |
| 2017 | 34.49 |
| 2018 | 35.16 |