| 年度 | 实际值 |
|---|---|
| 1992 | 17.31 |
| 1993 | 17.78 |
| 1994 | 18.18 |
| 1995 | 18.42 |
| 1996 | 18.89 |
| 1997 | 19.28 |
| 1998 | 19.92 |
| 1999 | 20.24 |
| 2000 | 205818 |
| 2001 | 207056 |
| 2002 | 27.9538 |
| 2003 | 21.0174 |
| 2004 | 21.1074 |
| 2005 | 21.1055 |
| 2006 | 20.82 |
| 2007 | 20.78 |
| 2008 | 21.58 |
| 2009 | 22.0612 |
| 2010 | 22.0127 |
| 2011 | |
| 2012 | 21.79 |
| 2013 | 21.72 |
| 2014 | 21.63 |
| 2015 | 22.66 |
| 2016 | 22.72 |