candidates from the Coalition parties and the Australian Labor Party. Alternative allocation methods for Senate For the Australian Senate, each State constitutes one multi-member electorate. Currently, 12 senators are elected from each State, one half every three years, except in the case of double dissolution when elections for all 12 senators in each State take place. The number of senators to be elected determines the 'quota' required to be achieved for election by quota-preferential voting. For a half-Senate election of 6 places to be filled, the quota in each State is 14.28% (calculated using the formula 1/(6+1)), while after a double dissolution the quota is 7.69% (calculated using the formula 1/(12+1)). The AEC also conducts a special recount after a double dissolution using a half-Senate quota for the purpose of allocating long and short terms so that rotation of senators can be re-established, however the Senate has never used the results to allocate terms, despite two bipartisan senate resolutions to use it. The federal Senate electoral system from 1984 to 2013, and those currently used for some state legislatures, provide for simultaneous registration of party-listed candidates and party-determined orders of voting preference, known as 'group voting tickets' or 'above the line voting' which involves placing the number '1' in a single box and the vote is then allocated in accordance with the party's registered voting preferences. The AEC automatically allocates preferences, or votes, in the predetermined order outlined in the group voting ticket. Each party or group can register up to three group voting tickets. This highly complex system has potential for unexpected outcomes, including the possible election of a candidate who may have initially received an insignificant primary vote tally (see, for example, the Minor Party Alliance at the 2013 federal election). An estimated 95% of all votes are cast 'above the line'. The alternative for Senate elections from 1984 to 2013 was to use 'below the line voting' by numbering a large number of individual candidate's boxes in the order of the voter's preference. To be valid, the voter placed sequential numbers against every candidate on the ballot paper, and the risk of error and invalidation of the vote was significant. In 2016, the Senate voting system was changed again to abolish group voting tickets and introduce optional preferential voting. An "above the line" vote for a party now allocates preferences to the candidates of that party only,