| 年度 | 实际值 |
|---|---|
| 1995 | 34.3 |
| 1996 | 36.2 |
| 1997 | 37.39 |
| 1998 | 37.8 |
| 1999 | 40.9 |
| 2000 | 42.5 |
| 2001 | 42.22 |
| 2002 | 41.81 |
| 2003 | 41.14 |
| 2004 | 40.61 |
| 2005 | 42.42 |
| 2006 | 41.78 |
| 2007 | 40.19 |
| 2008 | 40.29 |
| 2009 | |
| 2010 | 40.74 |
| 2011 | 40.47 |
| 2012 | 41.46 |
| 2013 | 40.22 |
| 2014 | 41.12 |
| 2015 | 43.69 |
| 2016 | 45.2 |
| 2017 | |
| 2018 | 46.85 |