| 年度 | 实际值 |
|---|---|
| 1995 | 28.4 |
| 1996 | 34.9 |
| 1997 | 44.31 |
| 1998 | 35 |
| 1999 | 36.6 |
| 2000 | 37.8 |
| 2001 | 38.7 |
| 2002 | 39.08 |
| 2003 | 40.87 |
| 2004 | 41.65 |
| 2005 | 41.68 |
| 2006 | 42.43 |
| 2007 | 45.46 |
| 2008 | 45.72 |
| 2009 | |
| 2010 | 46.81 |
| 2011 | 45.43 |
| 2012 | 45.96 |
| 2013 | 44.8 |
| 2014 | 46.84 |
| 2015 | 47.53 |
| 2016 | 48.57 |
| 2017 | 46.23 |
| 2018 | 46.82 |