If you walk down the streets in the United States, the odds are that one in every four people you’ll see is an immigrant, or was born to immigrant parents.

While those odds might seem high, the truth is nearly everyone in the U.S. hails from someplace else if you look far back enough.

Visualizing U.S. Immigration

Today’s intriguing visualization was created by professors Pedro M. Cruz and John Wihbey from Northeastern University, and it depicts U.S. immigration from 1830 until 2015, as rings in a growing tree trunk.

The researchers turned registered U.S. Census data into an estimate for the total number of immigrants arriving each decade, and then the yearly figures in the visualization. One caveat is that it does not account for the populations of slaves, or indigenous communities.

From the Old to the New World

The pattern of U.S. immigration can be explained in four major waves overall:

The origins of U.S. immigrant populations transform from era to era. Which events influenced each wave?

Frontier Expansion: 1830-1880

• Cheap farmland and the promise of economic growth in the first Industrial Revolution spurred large-scale immigration from Britain, Germany, and other parts of Central Europe.
• The Irish Potato Famine from 1845 to 1849 drove many immigrants from Ireland over to the U.S.
• The 1848 Treaty of Guadalupe ended the Mexican-American war, and extended U.S. citizenship to over 70,000 Mexican residents.

Industrialization: 1880-1915

• Immigrant mobility increased with the introduction of large steam-powered ships. The expansion of railroads in Europe also made it easier for people to reach oceanic ports.
• On the other hand, the Chinese Exclusion act in 1882 prohibited Chinese laborers from entry.
• In 1892, the famous Ellis Island opened; the first federal immigration station provided a gateway for over 12 million people.

The Great Pause: 1915-1965

• The Immigration Act of 1924 enacted quotas on immigrant numbers, restricting groups from countries in Southern and Eastern Europe, and virtually all immigrants of Asian origin.
• The Great Depression, and subsequent World Wars also complicated immigration matters as many came to seek refuge in the United States.

Post-1965 Immigration: 1965-Present

• The Hart-Cellber (Immigration and Naturalization Act) of 1965 overturned all previous quotas based on national origin. Family unification and an increase in skilled labor were two major aims of this act.
• This decision significantly impacted the U.S. demographic makeup in the following decades, as more immigrants of Latin, Asian, and African descent entered the country.

E Pluribus Unum (From Many, One)

While others have mapped two centuries of immigration before, few have captured its sheer scale and impact quite as strikingly. The researchers explain their reasoning behind this metaphor of tree rings:

This idea lends itself to the representation of history itself, as it shows a sequence of events that have left a mark and shaped the present. If cells leave a mark in the tree, so can incoming immigrants be seen as natural contributors to the growth of a trunk that is the United States.

It’s no wonder that this animation showing U.S. immigration won Gold for the “People, Language, and Identity” and “Most Beautiful” categories at the 2018 Kantar Information is Beautiful Awards.

How much happier would you be if were given a 10% raise?

While money can be a crucial indicator of happiness at lower income levels, studies have found that as incomes rise, money becomes a less important part of the overall happiness equation.

In fact, researchers see happiness as a complex measure that involves many variables outside of material wealth, including social support, freedom, and health.

Measuring Global Happiness

Today’s chart uses data from the World Happiness Report 2018 to measure and understand which countries report feeling the most and least happy.

WHAT CONTRIBUTES TO HAPPINESS?

The six key variables used by researchers in this report on global happiness include:

1. GDP per capita
2. Healthy life expectancy
3. Social support
4. Freedom of choice
5. Generosity
6. Perceptions of corruption

While average income and life expectancy definitely carry their weight in explaining happiness levels, what’s more interesting are the Gallup World Poll (GWP) questions about the other, more subjective variables.

• Social support
  “If you were in trouble, do you have relatives or friends you can count on to help you whenever you need them?”
• Freedom to make life choices
  “Are you satisfied or dissatisfied with your freedom to choose what you do with your life?”
• Generosity
  “Have you donated money to a charity in the past month?”
• Perceptions of corruption
  “Is corruption widespread throughout the government or not?”
  “Is corruption widespread within businesses or not?”

HOW HAPPY IS THE WORLD?

The top tier of happiest countries happen to be Nordic, with Finland, Norway, Denmark, and Iceland making it into the top five. Aside from having a common geographic location, these countries are also well-known for their social safety nets, using a high tax burden to fund government services such as education and healthcare.

A surprising entry near the top of the list might be Costa Rica. It’s the happiest country in the Latin American region, despite persisting income inequality issues. Although it has a lower GDP per capita than other high-ranking entries, the country has more than made up for it through social support; Costa Rica has invested significantly in education and health as a proportion of GDP, and the nation is also known for housing a culture that forms solid social networks of friends, families and neighborhoods.

On the other hand, 18 of the least happy countries are concentrated on the African continent. GDP per capita varies intensely among the bottom countries, and many report a lack of freedom overall. A silver lining is that social support is relatively stable, and there have been steady improvements over time.

Finally, the aftermath of the 2008 financial crisis has had a ripple effect on global happiness. The report demonstrates where the most and fewest advances have been made.

• Togo
  Happiness is on the upswing, as the West African nation climbs 17 places to demonstrate the most improvement.
• Venezuela
  Meanwhile, the South American country plummeted even further, in part from socio-political changes and dramatic hyperinflation.

Where does your country fare on this scale?

Eudaimonia [happiness] is the meaning and the purpose of life, the whole aim and end of human existence.

― Aristotle