| Year | Count |
|---|---|
| 1981 | 5 |
| 1983 | 7 |
| 1984 | 14 |
| 1985 | 20 |
| 1986 | 38 |
| 1987 | 32 |
| 1988 | 41 |
| 1989 | 41 |
| 1990 | 61 |
| 1991 | 161 |
| 1992 | 136 |
| 1993 | 147 |
| 1994 | 185 |
| 1995 | 221 |
| 1996 | 331 |
| 1997 | 516 |
| 1998 | 486 |
| 1999 | 449 |
| 2000 | 554 |
| 2001 | 618 |
| 2002 | 564 |
| 2003 | 654 |
| 2004 | 836 |
| 2005 | 928 |
| 2006 | 896 |
| 2007 | 989 |
| 2008 | 898 |
| 2009 | 769 |
| 2010 | 642 |
| 2011 | 766 |
| 2012 | 961 |
| 2013 | 879 |
| 2014 | 862 |
| 2015 | 929 |
| 2016 | 1,128 |
| 2016 | 6 |
| 2017 | 1,082 |
| 2017 | 5 |
| 2018 | 927 |
| 2019 | 1,019 |
| 2020 | 952 |
| 2021 | 968 |
| 2021 | 5 |
| 2022 | 969 |
| 2023 | 963 |
| 2024 | 847 |