Hi, consider the following example: <hansl> T = (2024-1990) * 4 nulldata T setobs 4 1991:1 --time-series open dbnomics # this is annual data ECB/ENA/A.N.DE.W0.S1.S1._Z.POP._Z._Z._Z.PS._Z.N --name="totalpop" </hansl> I was under the impression that the default for "data" is to repeat the low-frequency (here: annual) values when stuffing the data into a higher-frequency (here: quarterly) dataset. (Although I don't remember where I read that.) But with the above I'm getting this error message: '1991' does not match the format '%Y-%m-%d' Is this expected or a bug? thanks sven