| 年度 | 实际值 |
|---|---|
| 1995 | 45.6 |
| 1996 | 42.4 |
| 1997 | 42.61 |
| 1998 | 51.6 |
| 1999 | 50.7 |
| 2000 | 53.3 |
| 2001 | 54.75 |
| 2002 | 50.86 |
| 2003 | 52.14 |
| 2004 | 54.53 |
| 2005 | 55.13 |
| 2006 | 60.99 |
| 2007 | 67.37 |
| 2008 | 58.66 |
| 2009 | |
| 2010 | 56.17 |
| 2011 | 54.26 |
| 2012 | 52.28 |
| 2013 | 48.55 |
| 2014 | 46.9 |
| 2015 | 43.83 |
| 2016 | 44.68 |
| 2017 | 45.02 |
| 2018 | 44.34 |