| 年度 | 实际值 |
|---|---|
| 1995 | 38.7 |
| 1996 | 40.6 |
| 1997 | 42.08 |
| 1998 | 45.1 |
| 1999 | 46 |
| 2000 | 45.5 |
| 2001 | 46.57 |
| 2002 | 47.06 |
| 2003 | 45.46 |
| 2004 | 43.2 |
| 2005 | 41.49 |
| 2006 | 40.21 |
| 2007 | 40.54 |
| 2008 | 37.94 |
| 2009 | |
| 2010 | 45.95 |
| 2011 | 46.16 |
| 2012 | 46.99 |
| 2013 | 48.05 |
| 2014 | 49.34 |
| 2015 | 52.15 |
| 2016 | 56.44 |
| 2017 | |
| 2018 | 58.62 |