| Year | Count |
|---|---|
| 1959 | 6 |
| 1960 | 8 |
| 1962 | 5 |
| 1963 | 7 |
| 1964 | 10 |
| 1965 | 8 |
| 1966 | 5 |
| 1967 | 7 |
| 1968 | 5 |
| 1969 | 7 |
| 1970 | 8 |
| 1971 | 6 |
| 1972 | 5 |
| 1975 | 5 |
| 1977 | 6 |
| 1980 | 5 |
| 1981 | 5 |
| 1986 | 7 |
| 1989 | 6 |
| 1990 | 5 |
| 1991 | 5 |
| 1993 | 5 |
| 1994 | 6 |
| 1995 | 8 |
| 1996 | 8 |
| 1997 | 8 |
| 1998 | 7 |
| 1999 | 6 |
| 2000 | 8 |
| 2001 | 7 |
| 2003 | 5 |
| 2004 | 5 |
| 2005 | 8 |
| 2006 | 6 |
| 2008 | 8 |
| 2009 | 10 |
| 2010 | 10 |
| 2012 | 8 |
| 2013 | 7 |
| 2014 | 5 |
| 2015 | 11 |
| 2016 | 16 |
| 2017 | 18 |
| 2018 | 22 |
| 2019 | 32 |
| 2021 | 6 |
| 2022 | 8 |
| 2023 | 7 |
| 2024 | 9 |