Populism has taken root across the globe. These 4 charts explain why

2016 will be remembered as a year of populist political upsets.

The UK's Brexit vote in June and the election of President Donald Trump in November put nationalism centre stage in global politics.

Meanwhile, French National Front leader Marine le Pen is preparing for her own upset this year in Europe.

But the surge has been a long time coming, according to analysts at Deutsche Bank.

"For explaining vote choices, some analysts have stressed the connection between a sense of general pessimism among (parts of) the electorate and support for populists," Deutsche Bank economists Barbara Boetscher and Patricia Wruuck said in a note to clients on Friday.

The note features four illuminating charts that show just how populism came to be the dominant political movement of the modern West and traces its roots back to the early 2000s. Take a look at the charts below:

Populism has become tied up with a feeling that problems in one's own country are being made worse by problems in the rest of the world.

With that in mind, more people have looked to an authoritarian leader to focus on national, rather than international goals. Deutsche Bank said: "An important point here is that a negative outlook may induce people to opt for “the more risky choice”, i.e. the populist option, because they feel that they have suffered a loss already."

Populism and political extremism has been on the rise for years, especially in Europe. Both left and right wing authoritarians have been gaining in popularity.

Political populism is associated with government policy uncertainty. Brexit is a good example, because before a deal is struck, no-one knows what the economic outcome will be. "High levels of uncertainty have economic costs and work through various channels," Deutsche Bank said. "High political uncertainty is likely to pose impediments to investment because firms postpone decisions or reduce investment budgets."