| Year | Count |
|---|---|
| 1973 | 10 |
| 1974 | 36 |
| 1975 | 18 |
| 1976 | 22 |
| 1977 | 30 |
| 1978 | 32 |
| 1979 | 32 |
| 1980 | 26 |
| 1981 | 48 |
| 1982 | 16 |
| 1983 | 22 |
| 1984 | 16 |
| 1985 | 10 |
| 1986 | 18 |
| 1987 | 10 |
| 1988 | 22 |
| 1989 | 16 |
| 1990 | 20 |
| 1991 | 26 |
| 1992 | 16 |
| 1993 | 14 |
| 1994 | 12 |
| 1995 | 14 |
| 1997 | 26 |
| 1999 | 18 |
| 2000 | 18 |
| 2001 | 12 |
| 2002 | 18 |
| 2003 | 10 |
| 2004 | 14 |
| 2005 | 22 |
| 2006 | 12 |
| 2011 | 12 |
| 2012 | 12 |
| 2014 | 14 |
| 2018 | 10 |