Statistics by the workplace:
| Year of reporting | Count |
|---|---|
| 1966 | 1 |
| 1979 | 1 |
| 1980 | 4 |
| 1981 | 1 |
| 1982 | 1 |
| 1983 | 2 |
| 1984 | 2 |
| 1985 | 8 |
| 1986 | 8 |
| 1987 | 7 |
| 1988 | 10 |
| 1989 | 20 |
| 1990 | 62 |
| 1991 | 60 |
| 1992 | 86 |
| 1993 | 102 |
| 1994 | 540 |
| 1995 | 687 |
| 1996 | 657 |
| 1997 | 1143 |
| 1998 | 1474 |
| 1998. | 2 |
| 1999 | 1681 |
| 2000 | 1790 |
| 2001 | 1673 |
| 2002 | 1674 |
| 2003 | 1491 |
| 2004 | 2070 |
| 2005 | 2309 |
| 2006 | 1546 |
| 2007 | 2493 |
| 2008 | 2162 |
| 2009 | 2986 |
| 2010 | 3917 |
| 2011 | 2697 |
| 2012 | 2831 |
| 2013 | 3140 |
| 2014 | 2942 |
| 2015 | 2451 |
| 2016 | 2819 |
| 2017 | 2621 |
| 2018 | 2314 |
| 2019 | 2121 |
| 2020 | 1809 |
| 2021 | 1798 |
| 2022 | 1448 |
| 2023 | 1376 |
| 2024 | 380 |
| . | 2 |