| Year | Count |
|---|---|
| 1977 | 10 |
| 1978 | 54 |
| 1979 | 55 |
| 1980 | 69 |
| 1981 | 70 |
| 1982 | 44 |
| 1983 | 65 |
| 1984 | 25 |
| 1985 | 17 |
| 1986 | 24 |
| 1987 | 37 |
| 1988 | 15 |
| 1989 | 6 |
| 1990 | 26 |
| 1991 | 18 |
| 1992 | 34 |
| 1993 | 15 |
| 1995 | 34 |
| 1996 | 7 |
| 1997 | 50 |
| 1998 | 55 |
| 1999 | 68 |
| 2000 | 61 |
| 2001 | 54 |
| 2002 | 71 |
| 2003 | 54 |
| 2004 | 99 |
| 2005 | 199 |
| 2006 | 242 |
| 2007 | 246 |
| 2008 | 319 |
| 2009 | 277 |
| 2010 | 232 |
| 2011 | 326 |
| 2012 | 369 |
| 2013 | 415 |
| 2014 | 494 |
| 2015 | 746 |
| 2016 | 994 |
| 2017 | 1,274 |
| 2018 | 1,162 |
| 2019 | 922 |
| 2020 | 981 |
| 2021 | 1,118 |
| 2022 | 1,301 |
| 2023 | 1,534 |
| 2024 | 1,117 |