| Year | Count |
|---|---|
| 1975 | 5 |
| 1978 | 10 |
| 1979 | 16 |
| 1980 | 40 |
| 1981 | 18 |
| 1982 | 16 |
| 1983 | 20 |
| 1984 | 34 |
| 1985 | 34 |
| 1986 | 27 |
| 1987 | 42 |
| 1988 | 51 |
| 1989 | 64 |
| 1990 | 74 |
| 1991 | 85 |
| 1992 | 80 |
| 1993 | 71 |
| 1994 | 70 |
| 1995 | 87 |
| 1996 | 62 |
| 1997 | 74 |
| 1998 | 69 |
| 1999 | 50 |
| 2000 | 51 |
| 2001 | 64 |
| 2002 | 55 |
| 2003 | 35 |
| 2004 | 49 |
| 2005 | 37 |
| 2006 | 53 |
| 2007 | 50 |
| 2008 | 52 |
| 2009 | 67 |
| 2010 | 45 |
| 2011 | 41 |
| 2012 | 50 |
| 2013 | 32 |
| 2014 | 34 |
| 2015 | 30 |
| 2016 | 96 |
| 2017 | 81 |
| 2018 | 17 |
| 2019 | 28 |
| 2020 | 30 |
| 2021 | 40 |
| 2022 | 32 |
| 2023 | 24 |
| 2024 | 26 |