Sunspot numbers obtained by different networks in 2004 ====================================================== SIDC SONNE SONNE AAVSO AKS BAA GFOES GSRSI OAA RWG TOS VVS prov. prov. def. prov. (D) (GB) (F) (I) (J) (CH) (PL) (B) Jan 37.2 38.9 39.4 55.6 42.0 47.5 42.0 61.6 48.7 52.6 49.2 49.5 Feb 46.0 50.5 51.1 70.2 49.0 55.2 47.4 84.1 58.5 61.5 66.1 68.3 Mar 48.9 51.1 52.4 69.6 57.0 57.8 53.8 88.2 60.1 64.3 61.6 66.8 Apr 39.3 38.6 38.7 51.8 41.8 41.7 38.6 70.2 46.5 49.3 51.6 50.0 May 41.5 47.1 47.7 63.8 55.4 51.1 46.8 77.5 54.0 56.3 60.2 63.2 Jun 43.2 44.3 43.3 56.7 49.0 43.6 43.0 77.0 52.0 53.1 54.9 60.2 Jul 51.0 54.1 55.5 77.9 55.9 63.9 53.2 100.2 65.4 64.7 72.4 77.2 Aug 40.9 48.5 48.8 65.1 48.7 52.8 46.8 82.1 55.5 62.4 63.7 64.0 Sep 27.7 32.7 33.0 44.2 . 35.4 32.4 60.9 37.5 41.2 42.1 43.0 Oct 48.4 50.4 50.7 67.0 . 58.2 50.0 75.5 59.8 58.6 68.3 65.0 Nov 43.7 47.4 47.3 63.7 . 50.5 45.0 76.3 58.0 58.4 57.2 60.4 Dec 17.9 19.6 19.7 27.2 . 22.1 19.2 33.1 23.8 22.3 24.4 24.3 SIDC: Solar Influences Data Analysis Center, Brussels (International sunspot numbers) SONNE prov.: SONNE network, provisional sunspot numbers SONNE def. : SONNE network, definitive sunspot numbers AAVSO: American Association of Variable Star Observers - Solar Division AKS: Arbeitskreis Sonne des Kulturbundes e.V., Germany BAA: The British Astronomical Association - Solar Section, UK GFOES: G.F.O.E.S. Commission "Nombre de Wolf", France GSRSI: GruppoSole Ricerce Solari Italia, Italy OAA: The Oriental Astronomical Association - Solar Division, Japan RWG: Rudolf Wolf Gesellschaft - Solar Obs. Group of Swiss Astron. Society TOS: Towarzystwo Obserwatorow Slonca - Solar Observers Society, Poland VVS: Vereniging voor Sterrenkunde, Werkgroep Zon, Belgium