| Year | Count |
|---|---|
| 1975 | 10 |
| 1976 | 17 |
| 1977 | 45 |
| 1978 | 140 |
| 1979 | 212 |
| 1980 | 109 |
| 1981 | 87 |
| 1982 | 60 |
| 1983 | 51 |
| 1984 | 24 |
| 1985 | 30 |
| 1986 | 14 |
| 1987 | 6 |
| 1988 | 5 |
| 1990 | 5 |
| 1991 | 10 |
| 1993 | 6 |
| 1994 | 15 |
| 1995 | 5 |
| 1997 | 10 |
| 2002 | 5 |
| 2003 | 10 |
| 2004 | 5 |
| 2010 | 5 |
| 2011 | 5 |
| 2012 | 10 |
| 2013 | 15 |
| 2014 | 20 |
| 2015 | 14 |
| 2016 | 18 |
| 2019 | 6 |
| 2020 | 5 |
| 2021 | 10 |
| 2022 | 12 |
| 2023 | 8 |