| Year | Count |
|---|---|
| 1918 | 6 |
| 1919 | 15 |
| 1976 | 10 |
| 1979 | 5 |
| 1981 | 13 |
| 1982 | 24 |
| 1983 | 23 |
| 1984 | 26 |
| 1985 | 29 |
| 1986 | 44 |
| 1987 | 69 |
| 1988 | 62 |
| 1989 | 79 |
| 1990 | 73 |
| 1991 | 230 |
| 1992 | 259 |
| 1993 | 283 |
| 1994 | 260 |
| 1995 | 318 |
| 1996 | 288 |
| 1997 | 416 |
| 1998 | 453 |
| 1999 | 349 |
| 2000 | 402 |
| 2001 | 436 |
| 2002 | 365 |
| 2003 | 400 |
| 2004 | 581 |
| 2005 | 599 |
| 2006 | 552 |
| 2007 | 557 |
| 2008 | 512 |
| 2009 | 503 |
| 2010 | 425 |
| 2011 | 443 |
| 2012 | 415 |
| 2013 | 411 |
| 2014 | 305 |
| 2015 | 448 |
| 2016 | 323 |
| 2017 | 308 |
| 2018 | 208 |
| 2019 | 168 |
| 2020 | 149 |
| 2021 | 130 |
| 2022 | 98 |
| 2023 | 89 |
| 2024 | 88 |