Australia has compulsory voting, and a rather more complex election system where you have to state your order of preference of the candidates.

Some numbers from the recent election may be of relevance to those thinking about reform of the US electoral system, and purging bad data from the electoral rolls.

From The Australian :

A pointer to the numbers who vote only because they have to, or use their ballot to make a political protest, is the 21per cent of informal voters who left ballot papers blank in 2001 and the 6per cent who wrote slogans on them. But the AEC[Australian Electoral Commission] says some ballots may be left blank because people forget after first completing their Senate ballot or because they do not understand the voting system and would rather not vote at all than risk making a mistake.

Then there are those who do not vote at all, which is about 10 per cent of Australians older than 18. They include about 5 per cent of those on the electoral roll. After the 2001 election, the AEC scanned the roll and sent letters to almost 427,000 people asking why they had not voted. In most cases, it accepted the explanations, which included being overseas, in hospital or dead. About 40,000 people paid the $20 fine for failing to vote.

The other 5 per cent of non-voters are not on the roll, with the figure highest among the young. The AEC is trying to track them down by checking data at motor registries and Centrelink. Believe it or not, many 18-year-olds are more keen to get their driver’s licences and pick up their welfare payments than they are to get on the electoral roll.