| Year | Count |
|---|---|
| 1921 | 5 |
| 1925 | 5 |
| 1939 | 15 |
| 1975 | 11 |
| 1977 | 14 |
| 1978 | 21 |
| 1979 | 13 |
| 1980 | 11 |
| 1981 | 5 |
| 1982 | 31 |
| 1983 | 5 |
| 1984 | 5 |
| 1985 | 33 |
| 1986 | 11 |
| 1987 | 20 |
| 1988 | 6 |
| 1989 | 24 |
| 1990 | 25 |
| 1991 | 29 |
| 1992 | 44 |
| 1993 | 29 |
| 1994 | 86 |
| 1995 | 91 |
| 1996 | 95 |
| 1997 | 141 |
| 1998 | 338 |
| 1999 | 358 |
| 2000 | 364 |
| 2001 | 363 |
| 2002 | 346 |
| 2003 | 366 |
| 2004 | 397 |
| 2005 | 410 |
| 2006 | 455 |
| 2007 | 412 |
| 2008 | 498 |
| 2009 | 502 |
| 2010 | 525 |
| 2011 | 521 |
| 2012 | 728 |
| 2013 | 780 |
| 2014 | 867 |
| 2015 | 993 |
| 2016 | 1,298 |
| 2017 | 1,191 |
| 2018 | 1,358 |
| 2019 | 1,278 |
| 2020 | 976 |
| 2021 | 7 |
| 2021 | 1,257 |
| 2022 | 1,036 |
| 2023 | 833 |
| 2024 | 1,087 |