| Year | Count |
|---|---|
| 1980 | 5 |
| 1981 | 5 |
| 1983 | 5 |
| 1987 | 58 |
| 1988 | 285 |
| 1989 | 237 |
| 1990 | 296 |
| 1991 | 365 |
| 1992 | 283 |
| 1993 | 321 |
| 1994 | 249 |
| 1995 | 1,707 |
| 1996 | 2,010 |
| 1997 | 1,729 |
| 1998 | 1,700 |
| 1999 | 1,288 |
| 2000 | 956 |
| 2001 | 905 |
| 2002 | 673 |
| 2003 | 597 |
| 2004 | 607 |
| 2005 | 454 |
| 2006 | 390 |
| 2007 | 515 |
| 2008 | 315 |
| 2009 | 242 |
| 2010 | 151 |
| 2011 | 100 |
| 2012 | 63 |
| 2013 | 65 |
| 2014 | 80 |
| 2015 | 66 |
| 2016 | 54 |
| 2017 | 89 |
| 2018 | 56 |
| 2019 | 55 |
| 2020 | 79 |
| 2021 | 42 |
| 2022 | 55 |
| 2023 | 29 |
| 2024 | 14 |