Between May and July 2012, polyolefins prices decreased by around 20%, while polystyrene and PVC prices decreased by less. Between July and September, prices changed in almost the same but opposite direction; prices rose to their level at the beginning of the year; in October they decreased by around 5%; then they remained stable in a narrow range for the next five months; they also decreased slightly in April and May (Table 1, Figure 1).