| 年度 | 实际值 |
|---|---|
| 1995 | 30.3 |
| 1996 | 36.6 |
| 1997 | 42.63 |
| 1998 | |
| 1999 | 38.5 |
| 2000 | 40.3 |
| 2001 | 48.56 |
| 2002 | 53.99 |
| 2003 | 55.52 |
| 2004 | 55.91 |
| 2005 | 44.7 |
| 2006 | 46.67 |
| 2007 | 52.07 |
| 2008 | 43.71 |
| 2009 | |
| 2010 | 43.83 |
| 2011 | 52.43 |
| 2012 | 52.51 |
| 2013 | 53.95 |
| 2014 | 55.27 |
| 2015 | 55.11 |
| 2016 | 57.87 |
| 2017 | 57.24 |
| 2018 | 57.22 |