| 年度 | 实际值 |
|---|---|
| 1992 | 21969 |
| 1993 | |
| 1994 | |
| 1995 | 21102 |
| 1996 | |
| 1997 | |
| 1998 | |
| 1999 | 24155 |
| 2000 | 23360 |
| 2001 | 23270 |
| 2002 | 23185 |
| 2003 | 22199 |
| 2004 | 22756 |
| 2005 | 23044 |
| 2006 | 23814 |
| 2007 | 24804 |
| 2008 | 18366 |
| 2009 | 19070 |
| 2010 | 19313 |
| 2011 | 19664 |
| 2012 | 20496 |
| 2013 | 20851 |
| 2014 | 21042 |
| 2015 | 21053 |
| 2016 | 21387 |