| Year | Count |
|---|---|
| 1960 | 10 |
| 1963 | 18 |
| 1970 | 17 |
| 1974 | 12 |
| 1975 | 16 |
| 1976 | 45 |
| 1977 | 68 |
| 1978 | 47 |
| 1979 | 30 |
| 1985 | 14 |
| 1986 | 22 |
| 1988 | 17 |
| 1989 | 14 |
| 1990 | 5 |
| 1991 | 5 |
| 1992 | 30 |
| 1993 | 95 |
| 1994 | 90 |
| 1995 | 27 |
| 1996 | 33 |
| 1997 | 25 |
| 1998 | 16 |
| 1999 | 11 |
| 2000 | 5 |
| 2001 | 5 |
| 2002 | 12 |
| 2003 | 16 |
| 2005 | 15 |
| 2006 | 5 |
| 2008 | 5 |
| 2011 | 10 |
| 2014 | 5 |