Am 28.08.2026 um 14:10 schrieb Ramki S: First, I can confirm this, which is a (another) bug in the fcModels contributed package. Second, from the function signature of HoltDES, I believe that if you added 5 obs at the end of your dataset, then you might want to call the function with a value 5 as the last parameter. (Not 100% sure, since the function isn't very well documented.) Third, but the hard error is with the starting obs. I think the package uses the firstobs() hansl function incorrectly - the hansl function help clearly states that this only takes subsampling into account with the optional second arg set to 1/TRUE, which doesn't happen here. So I believe the package is broken with such subsampling. Fourth, as a workaround you could save your subsample to a new dataset file, starting at 1990, and work with that. (But I haven't tested it myself.) cheers sven