| 年度 | 实际值 |
|---|---|
| 1978 | 664 |
| 1979 | |
| 1980 | 228 |
| 1981 | |
| 1982 | |
| 1983 | |
| 1984 | |
| 1985 | 306 |
| 1986 | |
| 1987 | |
| 1988 | |
| 1989 | |
| 1990 | 199 |
| 1991 | |
| 1992 | |
| 1993 | |
| 1994 | |
| 1995 | 1129 |
| 1996 | |
| 1997 | |
| 1998 | |
| 1999 | 3487 |
| 2000 | 5670 |
| 2001 | 8755 |
| 2002 | 8791 |
| 2003 | 12498 |
| 2004 | 7239 |
| 2005 | 4182 |
| 2006 | 11388 |
| 2007 | 20055 |
| 2008 | 20204 |
| 2009 | 30884 |
| 2010 | 21670 |