| Year | Count |
|---|---|
| 1923 | 5 |
| 1969 | 5 |
| 1971 | 5 |
| 1981 | 9 |
| 1983 | 7 |
| 1991 | 6 |
| 1994 | 6 |
| 1995 | 18 |
| 1996 | 10 |
| 1997 | 22 |
| 1998 | 45 |
| 1999 | 30 |
| 2000 | 43 |
| 2001 | 109 |
| 2002 | 129 |
| 2003 | 134 |
| 2004 | 214 |
| 2005 | 304 |
| 2006 | 360 |
| 2007 | 401 |
| 2008 | 412 |
| 2009 | 494 |
| 2010 | 555 |
| 2011 | 615 |
| 2012 | 692 |
| 2013 | 624 |
| 2014 | 563 |
| 2015 | 357 |
| 2016 | 375 |
| 2017 | 255 |
| 2018 | 137 |
| 2019 | 91 |
| 2020 | 51 |
| 2021 | 49 |
| 2022 | 24 |
| 2023 | 30 |
| 2024 | 26 |