The term swing is organically employed in UK. It shows the extent of change in voter support typically from one election to another, expressed as a positive or negative percentage. In Australia however, swing is used in a different sense. For the Australian House of Representatives and the lower houses of the parliaments of all the Australian states and territories except Tasmania and the ACT, Australia employs preferential voting in single-member constituencies. Under the full-preference instant-runoff voting system, in each seat, the candidate with the lowest vote is eliminated and their preferences are distributed, which is repeated until only two candidates remain. Whilst every seat has a two-candidate preferred (TCP) result, seats where the major parties have come first and second are commonly referred to as having a two-party preferred (TPP) result. The concept of "swing" in Australian elections is not simply a function of the difference between the votes of the two leading candidates, as it is in Britain. To know the majority of any seat, and therefore the swing necessary for it to change hands, it is necessary to know the preferences of all the voters, regardless of who they give their first preference votes to. It is not uncommon in Australia for candidates who have comfortable leads on the first count to nevertheless fail to win the seat, because "preference flows" go against them.