| 年度 | 实际值 |
|---|---|
| 1992 | 32490 |
| 1993 | |
| 1994 | |
| 1995 | 30910 |
| 1996 | |
| 1997 | |
| 1998 | |
| 1999 | 30247 |
| 2000 | 25350 |
| 2001 | 21050 |
| 2002 | 19860 |
| 2003 | 18680 |
| 2004 | 18000 |
| 2005 | 18700 |
| 2006 | 18440 |
| 2007 | 18350 |
| 2008 | 15060 |
| 2009 | 16260 |
| 2010 | 16580 |
| 2011 | 16800 |
| 2012 | 16820 |
| 2013 | 16830 |
| 2014 | 14760 |
| 2015 | 13910 |
| 2016 | 13540 |