Graph
Year | Totals | Observation hours |
---|---|---|
1971 | 420 | 1:15 |
1972 | 0 | 0:30 |
1974 | 435 | 6:30 |
1977 | 0 | 2:30 |
1982 | 69 | 1:50 |
1983 | 1537 | 13:30 |
1984 | 2176 | 12:30 |
1985 | 1766 | 20:15 |
1986 | 0 | 2:00 |
1987 | 290 | 3:30 |
1988 | 200 | 3:15 |
1989 | 1215 | 9:30 |
1990 | 0 | 0:00 |
1991 | 0 | 4:30 |
1992 | 0 | 3:00 |
1993 | 60 | 6:46 |
1994 | 0 | 1:00 |
1995 | 1045 | 9:45 |
1996 | 300 | 5:15 |
1997 | 0 | 6:15 |
1998 | 600 | 6:30 |
1999 | 0 | 4:15 |
2000 | 235 | 8:45 |
2001 | 1650 | 24:00 |
2002 | 506 | 11:30 |
2003 | 95 | 6:14 |
2004 | 1598 | 52:15 |
2005 | 14966 | 370:45 |
2006 | 19964 | 560:00 |
2007 | 11249 | 568:00 |
2008 | 57531 | 623:30 |
2009 | 12970 | 346:10 |
2010 | 9339 | 257:51 |
2011 | 21271 | 379:30 |
2012 | 18587 | 474:30 |
2013 | 18730 | 449:30 |
2014 | 27202 | 366:57 |
2015 | 18882 | 241:57 |
2016 | 42633 | 386:02 |
2017 | 28425 | 309:56 |
2018 | 20570 | 319:16 |
2019 | 27280 | 243:15 |
2020 | 29551 | 304:06 |
2021 | 12497 | 186:53 |
2022 | 22878 | 219:44 |