| Year | Count |
|---|---|
| 1974 | 35 |
| 1976 | 24 |
| 1977 | 15 |
| 1978 | 49 |
| 1979 | 19 |
| 1980 | 48 |
| 1981 | 23 |
| 1982 | 28 |
| 1983 | 16 |
| 1984 | 31 |
| 1985 | 36 |
| 1986 | 32 |
| 1987 | 60 |
| 1988 | 39 |
| 1989 | 68 |
| 1990 | 33 |
| 1991 | 45 |
| 1992 | 37 |
| 1993 | 30 |
| 1994 | 39 |
| 1995 | 24 |
| 1996 | 34 |
| 1997 | 75 |
| 1998 | 42 |
| 1999 | 79 |
| 2000 | 69 |
| 2001 | 94 |
| 2002 | 66 |
| 2003 | 65 |
| 2004 | 10 |
| 2004 | 56 |
| 2005 | 88 |
| 2006 | 8 |
| 2006 | 131 |
| 2007 | 120 |
| 2008 | 382 |
| 2009 | 372 |
| 2010 | 491 |
| 2011 | 385 |
| 2012 | 494 |
| 2013 | 507 |
| 2014 | 585 |
| 2015 | 574 |
| 2016 | 631 |
| 2017 | 570 |
| 2018 | 6 |
| 2018 | 544 |
| 2019 | 473 |
| 2020 | 383 |
| 2021 | 414 |
| 2022 | 356 |
| 2023 | 351 |
| 2024 | 395 |