On Sat, 11 Apr 2009, Raz Lev wrote, in regard to adding a time-series variable to an existing panel dataset: And I responded with an illustrative script that would take the straight time-series CPI input and, via an intermediary matrix, "panelize" the data. That script was OK but I seriously missed a trick. Gretl is cleverer than you think! In fact all you have to do is use the "append" command. If the time-series length of the data you are appending matches the number of time periods in the panel, gretl automatically does the right thing -- no need to mess with matrices. I'd forgotten about that facility. Allin Cottrell