Graph
Year | Totals | Observation hours |
---|---|---|
1900 | 0 | 5:30 |
1980 | 2 | 2:00 |
1981 | 0 | 143:25 |
1982 | 0 | 100:04 |
1983 | 66 | 76:05 |
1984 | 488 | 157:55 |
1985 | 267 | 193:05 |
1986 | 493 | 180:40 |
1987 | 343 | 99:15 |
1988 | 42 | 216:00 |
1989 | 919 | 269:46 |
1990 | 2518 | 262:45 |
1991 | 2931 | 405:47 |
1992 | 1086 | 645:00 |
1993 | 668 | 397:58 |
1994 | 1455 | 286:00 |
1995 | 0 | 224:45 |
1996 | 1121 | 328:00 |
1997 | 1222 | 356:45 |
1998 | 738 | 339:30 |
1999 | 1 | 267:15 |
2000 | 106 | 261:30 |
2001 | 29 | 525:35 |
2002 | 3 | 526:15 |
2003 | 1 | 567:15 |
2004 | 0 | 455:05 |
2005 | 1363 | 601:15 |
2006 | 80 | 389:55 |
2007 | 116 | 432:55 |
2008 | 5 | 525:55 |
2009 | 401 | 399:05 |
2010 | 4 | 249:40 |
2011 | 0 | 319:15 |
2012 | 0 | 231:35 |
2013 | 16 | 270:55 |
2014 | 4 | 291:35 |
2015 | 0 | 177:30 |
2016 | 0 | 230:15 |
2017 | 0 | 250:05 |
2018 | 7 | 318:16 |
2019 | 166 | 584:19 |
2020 | 0 | 587:17 |
2021 | 0 | 646:27 |
2022 | 0 | 640:14 |