| 年度 | 实际值 |
|---|---|
| 1995 | 44.6 |
| 1996 | 44.7 |
| 1997 | 43.95 |
| 1998 | 44.1 |
| 1999 | 44.6 |
| 2000 | 43.3 |
| 2001 | 43.4 |
| 2002 | 43.94 |
| 2003 | 40.6 |
| 2004 | 43.16 |
| 2005 | 43.33 |
| 2006 | 45.56 |
| 2007 | 46.65 |
| 2008 | 50.62 |
| 2009 | |
| 2010 | 55.86 |
| 2011 | 59.46 |
| 2012 | 59.7 |
| 2013 | 59.03 |
| 2014 | 56.98 |
| 2015 | 54.83 |
| 2016 | 52.29 |
| 2017 | |
| 2018 | 48.21 |