The terms OPV and FPV are used mainly in Australia, in relation to elections at
state and territory and
Commonwealth (federal) level, which use
proportional representation (
Single transferable voting/STV) or
preferential voting (IRV). OPV is used in elections in the Australian state of
New South Wales. It was used in
Queensland's system of
instant-runoff voting from 1992 to 2015, when it was replaced by full-preferential voting. OPV was adopted in the
Northern Territory in 2016. In both the
Tasmanian House of Assembly and the
Tasmanian Legislative Council, semi-optional voting is used, with a minimum number of preferences required to be expressed. There is no requirement to complete the entire ballot paper (rank all the candidates). Elections for all other Australian lower houses use full-preferential voting. In the STV election of the
New South Wales Legislative Council, semi-optional preferential voting has been used since 1978, with a minimum 10 preferences required for 15 seats before 1991, and 15 preferences for 21 seats since. Voters also have the option since 1984 of voting "above the line". In the
Victorian Legislative Council, semi-optional preferential voting is used if a voter chooses to vote below the line. Voting above the line requires only a '1' being placed in one box, and
group voting tickets voting has applied since 1988. Around 1999 Melbourne's
Albert Langer engaged in a campaign to assist voters to mark fewer than all the candidates but still have their vote not deemed informal and rejected. This was a way to use the vote as if under the optional preferential voting system. The
Australian Senate voting reform of 2016 switched from full preferential voting to optional preferential voting. A minimum number is specified in the instructions on the ballot paper. Since in the past a single number '1' above the line was valid, that is still a formal vote even though voters are encouraged to rank six candidates. ==Elsewhere==