The easy explanation for the British vote for Brexit, Trump’s big electoral support and Le Pen’s presidential challenge in France is that the U.S. and Europe are experiencing a growth in “populism.”

These days, populism means the opposition by average, working people to traditional politics, which they see as having been run by an elite group. President Trump called his inauguration, “the day the people became the rulers of this nation again.”

It’s not as simple as that. Studies have determined who voted for Britain leaving the European Union, Trump gaining a strong enough popular vote to support an electoral victory, and the French being faced with the possibility of having Marine Le Pen as their extreme right-wing president.

Who supported Brexit, Trump and Le Pen and did they have anything in common? We now have solid, demographic information to answer those questions. A caution: despite the pundits, we will never know with this degree of certainty what was in people’s minds.

Brexit won with 52 percent of the vote last June. Its majority came as a surprise. Who supported Brexit, voting “Leave”? People who did not have post-high school education, older people and those in lower income areas. Older voters, remembering the long-past glory days of the U.K., decades before the EU, preferred the old ways.

Who favored remaining in the European Union? People whose jobs required higher education and people who lived in major cities. In London, 60 percent voted “Remain.”

The single, clearest demographic was education. If voters had gone to school beyond high school, they were more likely to vote for remaining in the EU. Younger voters supported “Remain,” but their turnout was lighter than for the general population.

The U.S. presidential election last November also produced a result that surprised many observers. Unlike the Brexit vote, it did not produce a popular majority for Trump (Clinton 48%, Trump 46%), though he was the Electoral College winner. Still, his popular vote was significant.

Counties where most people had no more than a high school education shifted toward Trump. As with Brexit, education was “the single most important variable,” according to researchers. Also similar to Brexit, Trump gained support from lower income areas and older voters.

Hillary Clinton overwhelmingly carried metropolitan areas of over one million people. She took New York City with 79 percent of the vote. But Trump carried every other municipal category. Many large cities are on the coast in the U.S., helping explain her seaboard domination.

One big difference between the U.K. and the U.S. was race. It was not a factor in the Brexit vote, while Trump carried the white vote and Clinton carried the nonwhite vote, almost traditional these days between the Republicans and the Democrats.

Finally, there was the French presidential election last Sunday between the centrist Emmanuel Macron and the extreme-right Marine Le Pen. Macron won 66%- 34%.

It’s worth looking at the Le Pen vote, because she openly sought support based on the Brexit and Trump surprise results. In France, there was no such surprise, though Le Pen did better than the far right had ever done in a presidential election.

Her supporters looked remarkably similar to the Brexit and Trump voters. London’s Financial Times found, “Education seems to the strongest predictor of the Macron vote.” The more people with a university degree, the more likely the vote where they were concentrated would go to Macron.

A similar election had taken place recently in the Netherlands, where the extreme right candidate won only 13 percent, and the same education factor was at play there.

As with the votes for Brexit and Trump, lower income people were more favorable to Le Pen than the population as a whole. But, as in the earlier votes, Macron overwhelmed Le Pen’s vote in the largest cities. In Paris, she received only 10 percent of the vote as France’s largest city rejected populism.

Another similarity in all three elections, plus the one in the Netherlands, was immigration, an issue that was clearly attractive to many Brexiters, Trump voters and Le Pen backers. In each case, though, the immigrants were widely different people.

Before the Brexit referendum, a pro-EU think tank wondered if the “Leave” supporters might be “Brexiting [themselves] in the foot.” People in areas most dependent on selling to the EU were the most opposed to it.

The same question may be asked in the U.S. Will Trump’s “America First” policies on trade, immigration, and affordable care insurance end up harming his supporters by their impact on prices, jobs and health?

Gordon Weil is a former public official. He lives in Harpswell.