| 年度 | 实际值 |
|---|---|
| 1993 | 37000 |
| 1994 | 38700 |
| 1995 | 39500 |
| 1996 | 40000 |
| 1997 | 40200 |
| 1998 | 39900 |
| 1999 | |
| 2000 | 34477 |
| 2001 | 27982 |
| 2002 | 24662 |
| 2003 | 21571 |
| 2004 | 20025 |
| 2005 | 19465 |
| 2006 | 17002 |
| 2007 | 18887 |
| 2008 | 21162 |
| 2009 | 26388 |
| 2010 | 28007 |
| 2011 | 29342 |
| 2012 | 30219 |
| 2013 | 26750 |
| 2014 | 28448 |
| 2015 | 29616 |
| 2016 | 29632 |
| 2017 | 29510 |