Sainte-Laguë method

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The Sainte-Laguë method, also called the Webster method (French pronunciation: [sɛ̃t.la.ɡy]), is a highest averages apportionment method for allocating seats in a parliament among federal states, or among parties in a party-list proportional representation system. The Sainte-Laguë method shows a more equal seats-to-votes ratio for different sized parties among apportionment methods.

The method was first described in 1832 by American statesman and senator Daniel Webster. In 1842, the method was adopted for proportional allocation of seats in United States congressional apportionment (Act of 25 June 1842, ch 46, 5 Stat. 491). The same method was independently invented in 1910 by the French mathematician André Sainte-Laguë.

It is used for party-list proportional representation in Ecuador, Germany, Indonesia, Kosovo, Latvia and Nepal, as well as in modified form in Norway and Sweden. It is also used as part of MMP in New Zealand.