*Excludes Observations that spanned multiple years
Pre 1970 | 24 |
---|---|
1970 | 11 |
1971 | 17 |
1972 | 11 |
1973 | 9 |
1974 | 7 |
1975 | 2 |
1976 | 7 |
1977 | 10 |
1978 | 5 |
1979 | 1 |
1980 | 4 |
1981 | 1 |
1982 | 1 |
1983 | 6 |
1984 | 2 |
1985 | 3 |
1986 | 9 |
1987 | 1 |
1988 | 92 |
1989 | 106 |
1990 | 79 |
1991 | 403 |
1992 | 249 |
1993 | 199 |
1994 | 544 |
1995 | 467 |
1996 | 288 |
1997 | 280 |
1998 | 353 |
1999 | 292 |
2000 | 604 |
2001 | 408 |
2002 | 578 |
2003 | 13 |
2004 | 4 |
2005 | 2 |
2006 | 11 |
2007 | 1 |
2008 | 0 |
2009 | 3 |
2010 | 13 |
2011 | 9 |
2012 | 8 |
2013 | 3 |
2014 | 13 |
2015 | 7 |
2016 | 4 |
2017 | 7 |
2018 | 4 |
2019 | 10 |
2020 | 4 |
2021 | 6 |
2022 | 0 |
Total | 5195 |