| Year | Count |
|---|---|
| 1917 | 6 |
| 1969 | 5 |
| 1975 | 9 |
| 1976 | 6 |
| 1977 | 6 |
| 1979 | 9 |
| 1982 | 5 |
| 1983 | 19 |
| 1984 | 18 |
| 1985 | 37 |
| 1986 | 65 |
| 1987 | 96 |
| 1988 | 80 |
| 1989 | 111 |
| 1990 | 96 |
| 1991 | 128 |
| 1992 | 156 |
| 1993 | 148 |
| 1994 | 196 |
| 1995 | 225 |
| 1996 | 229 |
| 1997 | 270 |
| 1998 | 365 |
| 1999 | 411 |
| 2000 | 446 |
| 2001 | 433 |
| 2002 | 446 |
| 2003 | 484 |
| 2004 | 517 |
| 2005 | 488 |
| 2006 | 494 |
| 2007 | 456 |
| 2008 | 613 |
| 2009 | 522 |
| 2010 | 594 |
| 2011 | 579 |
| 2012 | 598 |
| 2013 | 704 |
| 2014 | 688 |
| 2015 | 738 |
| 2016 | 872 |
| 2017 | 696 |
| 2018 | 711 |
| 2019 | 547 |
| 2020 | 492 |
| 2021 | 661 |
| 2022 | 522 |
| 2023 | 482 |
| 2024 | 445 |