Victory Thresholds of Representation
A variety of different formulas are used to translate votes into seats in full representation systems. For candidate-based systems – those systems that can be used in non-partisan races without parties – the threshold typically is established by the workings of the system rather than an electoral law. For these systems – cumulative voting and the one-vote version of limited voting -- and for the most common form of choice voting (with the "Droop" threshold), the thresholds to be guaranteed an opportunity to earn a seat are listed in the chart below. Note that in some circumstances candidates can win seats with a lower share of votes than this threshold, but can't be guaranteed such a win unless they win this share.

Number of Seats in District Threshold to Win One Seat
 One vote more than: 
 1 (winner-take-all)
 3 25.0%
 4 20.0%
 5 16.7%
 6 13.3%
 7 12.5%
 8 11.1%
 9 10.0%
 10 9.1%

These percentages are calculated using the following formula (known as the "Victory Threshold formula" or the "Droop" formula):

"Victory Threshold" =

1/(number of seats +1) x 100% + one more vote

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