| 年度 | 实际值 |
|---|---|
| 1995 | 43.6 |
| 1996 | 43.5 |
| 1997 | 35.62 |
| 1998 | 48.5 |
| 1999 | 46.1 |
| 2000 | 45.4 |
| 2001 | 44.79 |
| 2002 | 44.49 |
| 2003 | 46.24 |
| 2004 | 48.92 |
| 2005 | 52.24 |
| 2006 | 55.05 |
| 2007 | 57.65 |
| 2008 | 60.3 |
| 2009 | |
| 2010 | 59.79 |
| 2011 | 65.64 |
| 2012 | 64.58 |
| 2013 | 64.56 |
| 2014 | 62.51 |
| 2015 | 57.88 |
| 2016 | 55.22 |
| 2017 | 49.48 |
| 2018 | 49.77 |