| Year | Count |
|---|---|
| 1914 | 10 |
| 1918 | 14 |
| 1922 | 12 |
| 1933 | 5 |
| 1934 | 5 |
| 1947 | 5 |
| 1973 | 10 |
| 1974 | 40 |
| 1975 | 41 |
| 1976 | 59 |
| 1977 | 76 |
| 1978 | 167 |
| 1979 | 160 |
| 1980 | 166 |
| 1981 | 159 |
| 1982 | 147 |
| 1983 | 124 |
| 1984 | 138 |
| 1985 | 185 |
| 1986 | 144 |
| 1987 | 130 |
| 1988 | 168 |
| 1989 | 167 |
| 1990 | 213 |
| 1991 | 242 |
| 1992 | 288 |
| 1993 | 236 |
| 1994 | 282 |
| 1995 | 325 |
| 1996 | 261 |
| 1997 | 307 |
| 1998 | 364 |
| 1999 | 351 |
| 2000 | 348 |
| 2001 | 307 |
| 2002 | 272 |
| 2003 | 368 |
| 2004 | 338 |
| 2005 | 282 |
| 2006 | 314 |
| 2007 | 232 |
| 2008 | 209 |
| 2009 | 120 |
| 2010 | 147 |
| 2011 | 77 |
| 2012 | 15 |
| 2013 | 42 |
| 2014 | 36 |
| 2016 | 22 |