| 年度 | 实际值 |
|---|---|
| 1995 | 7.3 |
| 1996 | 10 |
| 1997 | 54.88 |
| 1998 | 11.3 |
| 1999 | 10.7 |
| 2000 | 7.3 |
| 2001 | 8.04 |
| 2002 | 9.75 |
| 2003 | 10.45 |
| 2004 | 11.04 |
| 2005 | 10.42 |
| 2006 | 10.59 |
| 2007 | 11.27 |
| 2008 | 12.76 |
| 2009 | |
| 2010 | 17.03 |
| 2011 | 14.1 |
| 2012 | 15.17 |
| 2013 | 16.64 |
| 2014 | 18.87 |
| 2015 | 29.06 |
| 2016 | 38.74 |
| 2017 | 35.51 |
| 2018 | 39.07 |