| Year | Count |
|---|---|
| 1975 | 5 |
| 1980 | 5 |
| 1981 | 8 |
| 1982 | 15 |
| 1983 | 17 |
| 1984 | 30 |
| 1985 | 51 |
| 1986 | 18 |
| 1987 | 26 |
| 1988 | 27 |
| 1990 | 21 |
| 1991 | 14 |
| 1992 | 69 |
| 1993 | 32 |
| 1994 | 27 |
| 1995 | 496 |
| 1996 | 1,326 |
| 1997 | 1,200 |
| 1998 | 1,132 |
| 1999 | 954 |
| 2000 | 1,036 |
| 2001 | 1,012 |
| 2002 | 1,144 |
| 2003 | 1,145 |
| 2004 | 2,224 |
| 2005 | 2,894 |
| 2006 | 1,791 |
| 2007 | 1,655 |
| 2008 | 1,558 |
| 2009 | 1,035 |
| 2010 | 887 |
| 2011 | 1,119 |
| 2012 | 1,020 |
| 2013 | 772 |
| 2014 | 622 |
| 2015 | 917 |
| 2016 | 822 |
| 2017 | 774 |
| 2018 | 602 |
| 2019 | 531 |
| 2020 | 503 |
| 2021 | 537 |
| 2022 | 627 |
| 2023 | 514 |
| 2024 | 456 |