| Year | Count |
|---|---|
| 1940 | 5 |
| 1959 | 7 |
| 1961 | 7 |
| 1964 | 7 |
| 1966 | 6 |
| 1967 | 6 |
| 1968 | 6 |
| 1972 | 13 |
| 1973 | 7 |
| 1981 | 34 |
| 1982 | 20 |
| 1983 | 9 |
| 1984 | 13 |
| 1985 | 7 |
| 1986 | 5 |
| 1987 | 11 |
| 1989 | 18 |
| 1990 | 11 |
| 1991 | 10 |
| 1992 | 19 |
| 1993 | 10 |
| 1994 | 20 |
| 1995 | 7 |
| 1996 | 28 |
| 1997 | 64 |
| 1998 | 44 |
| 1999 | 33 |
| 2000 | 38 |
| 2001 | 62 |
| 2002 | 54 |
| 2003 | 51 |
| 2004 | 65 |
| 2005 | 85 |
| 2006 | 80 |
| 2007 | 81 |
| 2008 | 117 |
| 2009 | 109 |
| 2010 | 67 |
| 2011 | 122 |
| 2012 | 61 |
| 2013 | 69 |
| 2014 | 80 |
| 2015 | 114 |
| 2016 | 172 |
| 2017 | 180 |
| 2018 | 110 |
| 2019 | 112 |
| 2020 | 64 |
| 2021 | 85 |
| 2022 | 58 |
| 2023 | 52 |
| 2024 | 52 |