The Election Day scene outside the Metropolitan African Methodist Episcopal Church in Northwest Washington on Nov. 8. (Photo by Marvin Joseph/The Washington Post)

Much has been made of the similarities between this week's election of Donald Trump to the White House and the British vote to leave the European Union just a few months before. There's good reason for this — both votes followed fierce campaigns dominated by debate over globalization and immigration, and both produced widely unexpected results that shocked much of the world.

Yet there are also a number of areas where the two votes don't look so alike.

And one may be especially surprising: Turnout.

Yes, despite the global political earthquakes both elections caused, the difference in turnout between the U.S. election on Nov. 8 and the Brexit referendum on June 23 is notable.

When it came time for Britain to make its historic vote on its continued membership of the E.U., 65.4 percent of voting age population headed to the polls.

But when it came time for Americans to vote in their own, similarly historic, election, it appears that around one in two eligible voters simply didn't turn up. While the final tally is still being counted, one estimate from the United States Election Project (USEP) suggested that turnout on Tuesday was around 56.9 percent, slightly down from 58.6 percent in 2012.

This relatively low turnout can have a pronounced affect on the outcome of the race. For example, though Donald Trump won the presidency after an unusually divisive and controversial campaign, he appears to have done so with fewer votes than Mitt Romney lost the election with in 2012.

The United States has long been unusual within the developed world for its low turnout in elections. For the past few decades, turnout with the voting eligible population during presidential elections has largely stayed stable between 50 and 60 percent. In midterm elections, it can be considerably worse: It was just 36.7 percent in 2014, the lowest in 72 years.

Earlier this year, Pew Research Center compiled recent voter turnout data from the International Institute for Democracy and Electoral Assistance (IIDEA) for developed countries. It found that the United States clearly lagged behind most of its peers when it came to turnout: It ranked 31st among the 35 countries in the Organization for Economic Cooperation and Development. The IIDEA data, which uses a slightly different calculation than the USEP data, found that 53.6 percent of the U.S. population voted in 2012. Meanwhile, Belgium had an 87.2 percent turnout rate in 2014, Turkey's was 84.3 percent in 2015, and Sweden's was 82.5 percent in 2014.

Why is the United States so far behind the pack? There are plenty of factors. For example, in some countries — including both Belgium and Turkey — voting is compulsory. The laws aren't necessarily strictly enforced (which is why you aren't seeing 99 percent turnout), but it still has a major effect.

Another is different policies on voter registration. Other developed countries have voters automatically registered as they become eligible. Alternatively, in many countries the government goes out of its way to find and register voters. However, in the United States, potential voters are expected to register themselves, and it's often not a simple process. Understandably, this results in a far lower proportion of registered voters: Just 65 percent of the voting age population is registered, Pew notes, compared to 91 percent in Britain and 96 percent in Sweden. While turnout among registered voters in the United States is fairly high — 84.3 percent in 2012 — the lower levels of registration mean that overall turnout remains low.

Timing is also a factor. U.S. elections are held on a Tuesday, when people generally have to work. For many, this is a huge inconvenience. “I’m at work all the time,” Eliza Holgate, a 19-year-old who works at a Golden Tan tanning salon in Utah, told the New York Times when asked to justify why she wasn't voting. Other countries with higher voter turnout than the United States, including France, Germany and Japan, hold their votes on the weekends. In some other countries, such as India, Election Day is a national holiday.

The 2016 election in the United States threw up other problems too. As Paul Waldman of The Plum Line notes, this was the first election in decades without the full protection of the 1965 Voting Rights Act. There are widespread accusations of voter suppression.

However, when contrasting the U.S. election with Britain's Brexit vote, it's also worth remembering the differences between the two votes. The Brexit vote was a single-issue referendum. Voters were asked a simple question: “Should the United Kingdom remain a member of the European Union or leave the European Union?” Ahead of the election, many had feared a low turnout, perhaps even lower than Britain's last general-election turnout of 61.1 percent, as it would be hard to persuade people who wanted to keep the status quo to vote.

In the end, turnout was far higher than most expected. It seems that people were aware of how important the vote was — and perhaps more notably, they felt passionately about their vote. In the U.S. election — one in which both of the major parties candidates had remarkably low favorability ratings — this passion may have been harder to summon.

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