Mathematics shows that every electoral system must compromise among proportionality, local representation, and parliament size. Germany’s attempt to protect both local representation and proportionality caused the Bundestag to expand sharply before reforms were introduced in 2023. Like many European democracies, Denmark uses a two-tier proportional system. New Zealand adopted proportional representation in 1993, but its House of Representatives does not have a fixed number of seats. Their method would determine each party’s total number of seats from its national vote share before geography is considered.