| 年度 | 实际值 |
|---|---|
| 1995 | 51.6 |
| 1996 | 54.7 |
| 1997 | 27.82 |
| 1998 | 41.7 |
| 1999 | 42.2 |
| 2000 | 41.5 |
| 2001 | 44.65 |
| 2002 | 39.83 |
| 2003 | 39.14 |
| 2004 | 37.22 |
| 2005 | 38.45 |
| 2006 | 38.23 |
| 2007 | 39.08 |
| 2008 | 38.53 |
| 2009 | |
| 2010 | 37 |
| 2011 | 36.18 |
| 2012 | 35.8 |
| 2013 | 37.22 |
| 2014 | 37.55 |
| 2015 | 39.3 |
| 2016 | 41.44 |
| 2017 | 43.08 |
| 2018 | 46.94 |