D'Hondt method

The D'Hondt method, also called the Jefferson method or the greatest divisors method, is an apportionment method for allocating seats in parliaments among federal states, or in proportional representation among political parties. It belongs to the class of highest-averages methods. Compared to ideal proportional representation, the D'Hondt method reduces somewhat the political fragmentation for smaller electoral district sizes, where it favors larger political parties over small parties.

The method was first described in 1792 by American Secretary of State and later President of the United States Thomas Jefferson. It was re-invented independently in 1878 by Belgian lawyer Victor D'Hondt, which is the reason for its two different names.