| 年度 | 实际值 |
|---|---|
| 1995 | 33.1 |
| 1996 | 36.7 |
| 1997 | 42.22 |
| 1998 | 43.8 |
| 1999 | 44.7 |
| 2000 | 44.2 |
| 2001 | 44.99 |
| 2002 | 43.88 |
| 2003 | 42.43 |
| 2004 | 40.68 |
| 2005 | 39.09 |
| 2006 | 39.28 |
| 2007 | 37.27 |
| 2008 | 38.31 |
| 2009 | |
| 2010 | 39.44 |
| 2011 | 39.46 |
| 2012 | 40.32 |
| 2013 | 41.46 |
| 2014 | 42.66 |
| 2015 | 44.03 |
| 2016 | 47.18 |
| 2017 | |
| 2018 | 58.81 |