version 10.1 mata: void avgper(string scalar vname, string scalar newvname, real scalar per, string scalar touse) { real matrix v1, v2, v3 st_view(v1=., ., vname, touse) st_view(v2=., ., newvname) v3 = colshape(v1', per) * J(per, 1, 1/per) v2[ (1::rows(v3)), ] = v3 } end