| Year | Count |
|---|---|
| 1915 | 10 |
| 1922 | 10 |
| 1924 | 18 |
| 1929 | 15 |
| 1931 | 18 |
| 1973 | 5 |
| 1974 | 6 |
| 1979 | 10 |
| 1980 | 8 |
| 1981 | 15 |
| 1982 | 13 |
| 1983 | 5 |
| 1984 | 6 |
| 1985 | 19 |
| 1986 | 7 |
| 1987 | 14 |
| 1988 | 12 |
| 1989 | 10 |
| 1990 | 16 |
| 1991 | 10 |
| 1992 | 13 |
| 1993 | 35 |
| 1994 | 29 |
| 1995 | 27 |
| 1996 | 56 |
| 1997 | 74 |
| 1998 | 41 |
| 1999 | 57 |
| 2000 | 91 |
| 2001 | 130 |
| 2002 | 185 |
| 2003 | 250 |
| 2004 | 12 |
| 2004 | 371 |
| 2005 | 409 |
| 2006 | 715 |
| 2007 | 6 |
| 2007 | 606 |
| 2008 | 774 |
| 2009 | 579 |
| 2010 | 551 |
| 2011 | 477 |
| 2012 | 431 |
| 2013 | 354 |
| 2014 | 382 |
| 2015 | 391 |
| 2016 | 395 |
| 2017 | 309 |
| 2018 | 235 |
| 2019 | 208 |
| 2020 | 236 |
| 2021 | 340 |
| 2022 | 231 |
| 2023 | 273 |
| 2024 | 195 |