Dear Allin, I have a 5 x 12 panel data that I processed, by mistake, as a 6 x 10 panel. Well, I tried to re-organize the panel structure but if I go through the "stacked time series" option no change takes place. Instead, if I select the "stacked cross section" everything works fine. regards, artur -- Artur BALA development economist, consultant phone: +216 22 99 73 44 skype: artur.bala.tn email: artur.bala.tn(a)gmail.com *********************************