Dear All, greetings from Paris ! I am currently using the seasonal adjustment facilities in Gretl, either the tramo or X12 Arima analyses directly or throught the arima modelling tool (using X12 option). However, it seems that both X12 and tramo parameters are set to default values and cannot be modified via the gretl interface. Is it the case, and could it be done, maybe via the programs themselves ? Thanx in advance for your kind response. For those of you interested in seasonal adjustment, let me share an interesting finding: the DEMETRA facility. This is a seasonal adjustment software developped by Eurostat for the community, it is available free of charge at the following link: http://forum.europa.eu.int/Public/irc/dsis/eurosam/library?l=/software/de... presentation of the project here: http://forum.europa.eu.int/irc/dsis/eurosam/info/data/demetra.htm A final note, the software implements both tramo-seats and x12 arima in a transparent and extensive way and can manage large projects. It proposes many diagnosis tools and information on the two methodologies, originating from the work of the informal working group on seasonal adjustment in eurostat. DEMETRA allows and is design to implement and compare both methods. sincerely, and continue the wonderful job ! Franck Franck -- Franck Nadaud CIRED Centre International de Recherche sur l'environnement et le Développement CNRS EHESS UMR 8568 Campus du Jardin Tropical de Paris 45 bis avenue de la Belle Gabrielle 94736 Nogent sur Marne Cedex Tél : 01 43 94 73 94 (ligne directe) FAX : 01 43 94 73 70