The Spanish electoral system: Proportionality and governability

This paper briefly describes the formulation of the apportionment problem, the principal techniques involved in electoral methods and some d'Hondt and St. Laguë properties. We then illustrate the high disproportionality of Spain's electoral system over seven general elections and its consequences for the major political parties. We propose to increase proportionality by means of a complementary second apportionment with minimal requirements. Moreover, to enhance governability, we propose to award a bonus percentage of seats, similar to that afforded under the present system, to the winning party. The proposed technique for improving proportionality while maintaining the present advantage to the winning party can be applied in other democratic systems with low proportionality between total votes and total seats obtained.