The last example is based on four parties, assuming that each constituency is fought by the three main parties (PSOE, PP, IU) plus a nationalist or regional one. However this is an approximation. The results vary considerably. All that can be concluded is that a party that exceeds these figures has a very good chance of being elected whereas below this level the situation is much less certain. A more detailed examination of the Spanish situation, which is quite topical, highlights the difficulty.