| Year | Count |
|---|---|
| 1980 | 13 |
| 1981 | 12 |
| 1982 | 54 |
| 1983 | 110 |
| 1984 | 123 |
| 1985 | 326 |
| 1986 | 506 |
| 1987 | 653 |
| 1988 | 1,347 |
| 1989 | 1,541 |
| 1990 | 1,778 |
| 1991 | 2,167 |
| 1992 | 2,285 |
| 1993 | 2,411 |
| 1994 | 2,685 |
| 1995 | 2,765 |
| 1996 | 2,776 |
| 1997 | 2,875 |
| 1998 | 3,874 |
| 1999 | 2,969 |
| 2000 | 3,201 |
| 2001 | 2,654 |
| 2002 | 2,404 |
| 2003 | 2,268 |
| 2004 | 2,704 |
| 2004 | 20 |
| 2005 | 2,515 |
| 2006 | 2,198 |
| 2007 | 2,019 |
| 2008 | 1,785 |
| 2009 | 1,399 |
| 2010 | 1,085 |
| 2011 | 1,092 |
| 2012 | 918 |
| 2013 | 773 |
| 2014 | 682 |
| 2015 | 558 |
| 2016 | 243 |
| 2017 | 278 |
| 2018 | 161 |
| 2019 | 154 |
| 2020 | 98 |
| 2021 | 85 |
| 2022 | 76 |
| 2023 | 65 |
| 2024 | 13 |