| Year | Count |
|---|---|
| 1965 | 5 |
| 1978 | 10 |
| 1979 | 12 |
| 1980 | 38 |
| 1981 | 19 |
| 1982 | 9 |
| 1983 | 11 |
| 1984 | 13 |
| 1985 | 21 |
| 1986 | 296 |
| 1987 | 122 |
| 1988 | 55 |
| 1989 | 78 |
| 1990 | 82 |
| 1991 | 132 |
| 1992 | 120 |
| 1993 | 117 |
| 1994 | 110 |
| 1995 | 87 |
| 1996 | 157 |
| 1997 | 182 |
| 1998 | 235 |
| 1999 | 247 |
| 2000 | 386 |
| 2001 | 434 |
| 2002 | 591 |
| 2003 | 770 |
| 2004 | 1,128 |
| 2005 | 1,254 |
| 2006 | 1,296 |
| 2007 | 1,579 |
| 2008 | 1,775 |
| 2009 | 1,639 |
| 2010 | 1,762 |
| 2011 | 2,266 |
| 2012 | 2,441 |
| 2013 | 2,537 |
| 2014 | 2,683 |
| 2015 | 3,182 |
| 2016 | 3,808 |
| 2017 | 3,945 |
| 2018 | 3,871 |
| 2019 | 4,135 |
| 2020 | 4,086 |
| 2021 | 4,957 |
| 2022 | 5,537 |
| 2023 | 6,165 |
| 2024 | 7,163 |