| 年度 | 实际值 |
|---|---|
| 1995 | 48.1 |
| 1996 | 42.6 |
| 1997 | 44.04 |
| 1998 | 43.3 |
| 1999 | 45.8 |
| 2000 | 44.2 |
| 2001 | 42.76 |
| 2002 | 33.58 |
| 2003 | 34.61 |
| 2004 | 36.37 |
| 2005 | 39.47 |
| 2006 | 40.25 |
| 2007 | 39.92 |
| 2008 | 38.58 |
| 2009 | |
| 2010 | 39.14 |
| 2011 | 41.33 |
| 2012 | 42.46 |
| 2013 | 45.1 |
| 2014 | 46.21 |
| 2015 | 44.03 |
| 2016 | 42.8 |
| 2017 | |
| 2018 | 47.7 |