Demographics
Timeline: Key Events in U.S. History that Defined Generations

Introducing our new index, which ranks U.S. generations on their economic, political, and cultural influence.

Key Events in U.S. History that Defined Generations
Looking back at history is a necessity when trying to understand what the future may hold.
Using insights from our Generational Power Index 2021 report, along with survey data from Pew Research in 2016, we identified some key milestones for each cohort, to understand how these events helped shape each generation’s unique perspectives.
Quick Context on Generational Definitions
Before diving in, it’s important to clarify which generations we’ve included in our research, along with their age and birth year ranges.
Generation | Age range (years) | Birth year range |
---|---|---|
The Silent Generation | 76 and over | 1928-1945 |
Baby Boomers | 57-75 | 1946-1964 |
Gen X | 41-56 | 1965-1980 |
Millennials | 25-40 | 1981-1996 |
Gen Z | 9-24 | 1997-2012 |
Gen Alpha | 8 and below | 2013-present |
These generational categories aren’t universal, but we went with the most widely cited definitions from reputable U.S. sources including the Pew Research and the U.S. Federal Reserve. It’s also worth noting that these generational definitions are somewhat specific to North America. For this reason, the focus is on U.S. historic events.
Defining Events: Silent Generation
The oldest members of the Silent Generation were 11 years old at the start of World War II, and were teenagers by the time it ended. In other words, their formative years fell smack dab in the middle of one of the biggest international conflicts in modern history.
Because of this, it makes sense that World War II ranks as the second most impactful event in their lifetimes, trailing only the far more recent Sept. 11 terrorist attacks (2001).
Most Impactful Historic Events, Silent Gen (Survey Results)
Rank | Silent Gen | Survey % |
---|---|---|
#1 | Sept. 11 | 59% |
#2 | WWII | 44% |
#3 | JFK Assassination | 41% |
#4 | Vietnam War | 37% |
#5 | Moon landing | 29% |
#6 | Obama election | 28% |
#7 | The tech revolution | 27% |
#8 | Civil rights movement | 18% |
#9 | Korean War | 18% |
#10 | Iraq/Afghanistan wars | 14% |
In fact, the Silent Generation cited four different wars on their list, more than any other cohort. For context, Boomers identified three conflicts (including the Cold War), while Millennials only referenced one (Iraq/Afghanistan).
Of course, other not-so-violent events made the list as well. And interestingly, some of these impressionable moments occurred later on in life.
For example, the youngest members of The Silent Generation were already in their mid-t0-late forties when cellphones became common in the ‘90s—yet, 27% identified the tech revolution as one of the top 10 most impactful events that happened in their lifetime.
Clearly, life never stops throwing you curve balls—no matter how far along you might be.
Most Notable Historical Events: Baby Boomers
Many of the historical experiences cited by Baby Boomers were related to war and violent acts. For instance, Boomers identified two assassinations on their list—John F. Kennedy’s in 1963, and Martin Luther King’s in 1968.
Most Impactful Historic Events, Boomers (Survey Results)
Rank | Baby Boomers | Survey % |
---|---|---|
#1 | Sept. 11 | 70% |
#2 | JFK Assassination | 45% |
#3 | Vietnam War | 41% |
#4 | Obama election | 38% |
#5 | Moon landing | 35% |
#6 | The tech revolution | 26% |
#7 | Civil rights movement | 18% |
#8 | Fall of Berlin Wall/end of Cold War | 16% |
#9 | MLK assassination | 15% |
#10 | Iraq/Afghanistan wars | 11% |
For this generation, the moon landing in 1969 made the cut, as did Barack Obama’s election win in 2008.
Baby Boomers only identified one event that was unique to their cohort (Martin Luther King’s death). It’s worth noting that responses varied between Americans of different racial backgrounds. Not surprisingly, Black Americans were far more likely to name MLK’s death as a top defining moment.
Most Notable Historical Events: Gen X
For Gen Xers, two unique events made their list: the Challenger disaster (1986) and the Gulf War (1991). Interestingly, neither of of these events stood out for other generations.
The Challenger disaster impact was widely felt because it involved civilians alongside astronauts, making the space shuttle’s explosion all the more notorious.
Most Impactful Historic Events, Gen Xers (Survey Results)
Rank | Gen X | Survey % |
---|---|---|
#1 | Sept. 11 | 79% |
#2 | Obama election | 40% |
#3 | Fall of Berlin Wall/end of Cold War | 21% |
#4 | The tech revolution | 20% |
#5 | Iraq/Afghanistan wars | 18% |
#6 | Gulf War | 15% |
#7 | Challenger disaster | 14% |
#8 | Gay marriage | 10% |
#9 | Hurricane Katrina | 10% |
#10 | Columbine shooting | 9% |
#11 | Orlando shooting | 9% |
#12 | Oklahoma City bombing | 9% |
Hurricane Katrina (which occurred in 2005) is the only natural disaster to make it on any of these lists. The hurricane—which caused a significant share of New Orleans’ population to resettle—left a lasting impression on the nation.
Most Notable Historical Events: Millennials
Millennials remember the September 11 attacks the most of all generations, with 86% citing it as their most influential event. They also paid close attention to the aftermath of this occurrence, as marked by the inclusion of both the Iraq/Afghanistan wars and the death of Osama Bin Laden among their most notable events.
Most Impactful Historic Events, Millennials (Survey Results)
Rank | Millennials | Survey % |
---|---|---|
#1 | Sept.11 | 86% |
#2 | Obama election | 47% |
#3 | Iraq/Afghanistan wars | 24% |
#4 | Gay marriage | 19% |
#5 | The tech revolution | 18% |
#6 | Orlando shooting | 17% |
#7 | Hurricane Katrina | 11% |
#8 | Columbine shooting | 10% |
#9 | Bin Laden | 10% |
#10 | Sandy Hook | 7% |
#11 | Boston Marathon bombing | 7% |
#12 | Great Recession | 7% |
Sadly, a lot of Millennials recollect instances of gun violence more than any other generation, from Orlando and Columbine to Sandy Hook.
Last but not least, Millennials are the only generation to note the Global Financial Crisis of 2008, and the subsequent Great Recession, as a momentous event. This makes sense considering many of them began their careers in its aftermath.
Gen Z and Younger
The Pew Research survey data was collected in 2016, so opinions on more recent events have not been collected.
That said, it could be premature to say in the short term which events will leave a lasting impression on generations, young and old.
According to the above data, the election of Barack Obama was a lasting milestone in recent history. Will the election of Donald Trump leave a similar impact? How will COVID-19 be regarded in the future? Time will tell which events will define future generations.
Moments, Movements, and Everything in Between
One key takeaway worth emphasizing is just how varied these formative events can be. Some were experienced as a single moment, while others were a culmination of shifts over several years.
It’s also clear that timing and duration are not the only determining factors behind an event’s influence on American society. For example, the moon landing was a tangible moment with a date stamp, whereas the tech revolution has a much fuzzier start (before exploding in significance alongside the Dotcom boom and bust).
Also interesting is what is absent from the top results. For example, the Global Financial Crisis of 2008 is barely referenced.
In short, a variety of impactful events and more gradual revolutions have made their mark on American society. Some have influenced specific generations, while others have transcended generational boundaries and unified the American public.
Download the Generational Power Report (.pdf)
For a full methodology of how we built the Generational Power Index, see pages 28-30 in the report PDF. This is the first year of the report, and any feedback is welcomed.
Demographics
Comparing Population Pyramids Around the World
Population pyramids can show a country’s demographic advantages and challenges at a glance. See how different parts of the world stack up.

Understanding and Comparing Population Pyramids
Demographic data can reveal all kinds of insights about a population, from the country’s fertility and mortality rates to how certain events and policies have shaped the makeup of a population.
Population pyramids are one of the best ways to visualize population data, and comparing the pyramids of various countries and regions side-by-side can reveal unexpected insights and differences between groups.
This graphic uses population data from the United Nations to compare the demographics of some select nations and regions of the world, showcasing how much age distributions can vary.
Three Types of Population Pyramids
Although population pyramids can come in all shapes and sizes, most generally fall into three distinct categories:
- Expansive Pyramids: Recognized by their traditional “pyramid-like” shape with a broad base and narrow top, expansive pyramids reflect a population with a high birth rate along with a high mortality rate which is most common in developing countries.
- Constrictive Pyramids: With a narrow base and thicker middle and top sections of the pyramid, constrictive pyramids often occur in developed economies whose populations have low birth rates and long life expectancies.
- Stationary Pyramids: These pyramids showcase an evenly distributed population across age groups, often found in newly-developed countries which have stable birth and mortality rates.
Each population pyramid is essentially a visual snapshot of a nation’s current demographic breakdown, shaped by fluctuating birth and mortality rates as well as changes to immigration and social policies.
Understanding the inherent risks associated with different pyramid types can help give insight into the challenges these populations face.
The Risks of Different Population Pyramid Types
Each type of population pyramid structure has unique challenges and advantages often characterized by the country or region’s current stage of economic development.
Populations with expansive pyramids, such as the one representing the continent of Africa, have the advantage of a larger youth and working-aged population, however this advantage can be rendered null if job growth, education, and health care aren’t prioritized.
Countries with constrictive pyramids like Japan face the challenge of supporting their outsized aging population with a diminishing working-aged population. While immigration and increasing birth rates can help in both the short and long term, due to the working population being outnumbered, countries with constrictive pyramids must find ways to increase their productivity to avoid potential declines in economic growth.
China and India’s Demographics Compared
After the world’s population reached eight billion people last year, 2023 brought a new population milestone as India overtook China as the world’s most populous country.
When you compare the two nations’ population pyramids, you can see how India’s population has a strong base of young and working-aged people compared to China’s more constrictive population pyramid that also features a higher median age.
This demographic difference is largely shaped by China’s one-child policy which since 2021 was loosened to be a three-child policy. As a result, China’s total fertility rate is around 1.2 today, in contrast to India’s total fertility rate of 2.0.
While India is set to ride the productivity boom of its large working-age population, the country will have to ensure it can keep its population pyramid stable as the majority of the population ages and total fertility rates continue to decline.
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Interested in learning more about the various factors that affect demographics?
VC+ Members get an exclusive look comparing the G7 and BRICS nations, how war shapes population pyramids, and immigration’s role in demographics. Unlock this in-depth briefing and hundreds of other visual insights with our newly available VC+ Archive. |
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