| Year | Count |
|---|---|
| 1921 | 5 |
| 1973 | 8 |
| 1975 | 35 |
| 1977 | 18 |
| 1978 | 25 |
| 1979 | 5 |
| 1981 | 30 |
| 1982 | 5 |
| 1983 | 26 |
| 1984 | 40 |
| 1985 | 11 |
| 1986 | 8 |
| 1987 | 30 |
| 1988 | 30 |
| 1989 | 31 |
| 1990 | 39 |
| 1991 | 45 |
| 1992 | 40 |
| 1993 | 41 |
| 1994 | 46 |
| 1995 | 24 |
| 1996 | 45 |
| 1997 | 57 |
| 1998 | 80 |
| 1999 | 66 |
| 2000 | 98 |
| 2001 | 107 |
| 2002 | 116 |
| 2003 | 144 |
| 2004 | 160 |
| 2005 | 205 |
| 2006 | 266 |
| 2007 | 244 |
| 2008 | 300 |
| 2009 | 278 |
| 2010 | 267 |
| 2011 | 313 |
| 2012 | 343 |
| 2013 | 330 |
| 2014 | 344 |
| 2015 | 386 |
| 2016 | 431 |
| 2017 | 461 |
| 2018 | 486 |
| 2019 | 578 |
| 2020 | 544 |
| 2021 | 776 |
| 2022 | 579 |
| 2023 | 614 |
| 2024 | 765 |