| 年度 | 实际值 |
|---|---|
| 1993 | 49000 |
| 1994 | 49800 |
| 1995 | 48800 |
| 1996 | 50000 |
| 1997 | 48600 |
| 1998 | 47800 |
| 1999 | |
| 2000 | 43456 |
| 2001 | 40272 |
| 2002 | 37287 |
| 2003 | 33227 |
| 2004 | 30250 |
| 2005 | 27280 |
| 2006 | 24964 |
| 2007 | 22820 |
| 2008 | 21300 |
| 2009 | 20211 |
| 2010 | 20430 |
| 2011 | 20603 |
| 2012 | 21184 |
| 2013 | 21083 |
| 2014 | 21147 |
| 2015 | 21194 |
| 2016 | 20580 |
| 2017 | 19696 |