Electoral Systems of the World

Following the recent election, there has been much talk about electoral reform in the UK. At least one national newspaper has been vigorously campaigning for the introduction some form of Proportional Representation (PR). It's cropped up in a few places in the nascent British political blogosphere, too.

A few days ago, in conversation, someone voiced the concerns of many by pointing to the example of Israel, where (from an outsider's perspective) it appears that fragile parliamentary coalitions, desparate for a few extra votes, are held to ransom by tiny minority parties. The scare story that sprang to my mind was the famously unstable Italian system, where it seemed unusual for a single government to last more than 18 months, with similar minor-party brinkmanship (though they seem to have reformed their system in the '90s and have since managed stability broadly comparable to most other Western European states)

So, are these examples a fair characterisation of PR systems? Just how many countries use PR anyhow? So off I went, and spent far too much of one evening last week doing research into electoral systems in use the world over. Below is a table listing the electoral systems of about 20 of the world's democratic countries. I've mostly aimed at large(ish) countries that have been democratic for several decades, though the list includes some exceptions to both rules.

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