In Belgium,Bosnia and Herzegovina, Bulgaria, Latviaand Norway inter alia, the voters can express as many preferences as there are candidates in the selected party list and the candidates elected are reordered and ranked based on the individual votes they obtained through the preferences expressed by the voters. In Belgium, in the case of both Chambers, the votes of voters who have not cast a preference vote are automatically considered to be preference votes in favour of the candidates at the top of the lists. In Bosnia and Herzegovina, the electoral system is partly a closed-list system, partly an openlist system, depending if a candidate list obtains more (open-list system) or less (closed-list system) than 3% of the votes cast. Moreover, if a party or a coalition does not have enough eligible candidates on the list to fill seats allocated to it, the mandate shall be transferred to the party or coalition list in another constituency. In Bulgaria, it has been noted during the last parliamentary elections that an unusual number of ballots have been declared (rightly) invalid as many voters expressed preferences but omitted to vote for the party list. Even if their choice may have been logically deducted from the preferences expressed, the ballots concerned were invalidated.