There appears to be a single "\n" missing from the body of stats:::summary.stl, causing the "Time.series components" and "IQR" sections to butt up against each other. The fix should be to simply switch cat(" IQR:\n") for cat("\n IQR:\n") While looking at this function I wondered: Has it been considered to include a printout of explained variance? For example, following the IQR pattern: cat("\n Variance:\n") exv <- apply(cbind(STL = object$time.series, data = object$time.series %*% rep(1, 3)), 2L, var) print(rbind(format(exv, digits = max(2L, digits - 3L)), ` %` = format(round(100 * exv/exv["data"], 1))), quote = FALSE) ?Aksel