| 年度 | 实际值 |
|---|---|
| 1992 | 16.6 |
| 1993 | |
| 1994 | |
| 1995 | 15.9 |
| 1996 | |
| 1997 | |
| 1998 | |
| 1999 | 16.5 |
| 2000 | 165015 |
| 2001 | 164836 |
| 2002 | 14.4699 |
| 2003 | 14.7115 |
| 2004 | 14.6982 |
| 2005 | 14.7227 |
| 2006 | 14.79 |
| 2007 | 15.14 |
| 2008 | 15.33 |
| 2009 | 15.4639 |
| 2010 | 15.6297 |
| 2011 | 15.7455 |
| 2012 | 15.85 |
| 2013 | 16.07 |
| 2014 | 16.34 |
| 2015 | 16.89 |
| 2016 | 14.75 |