The median household income in the US was $52,250 in 2013, according to the Census Bureau. Chances are that number leaves you feeling rich, poor, or average. Though the number is based on millions of households, it’s too boiled down to mean much.

On the other hand, if you had a list of the more than 100 million household incomes, that wouldn’t help much, either. County medians, plus BatchGeo’s clustering technology, turns out to be a great way to gain insights from the data.

View 2013 Median US Household Income in a full screen map

At the initial zoom level, you should see around a dozen clusters represented by pie charts and a dollar figure. The pie slices show the ratio of counties within each cluster that fall within each income range. The dollar value for each cluster is the average of the county medians. While it’s not weighted by population, it should give a good snapshot of income across the country.

Incomes are highest along the west and east coasts. Zoom, click, and filter the map to start gaining deeper insights. For example, California accounts for a lot of the high average along the west, though the Salt Lake City and Denver / Colorado Springs areas also have high median incomes. There’s a similar cluster along the northeast, as well.

Throughout the south the averages of county medians are lower, but you can also see the ratio of lower range salaries are much higher, especially in the southeast. If you zoom in, you’ll see large sections of Mississippi and Alabama that are entirely made up of the lowest ranges. By comparison, California has only three counties with median incomes below $40,000 (the bottom three ranges).

Switch to grouping by poverty level and the pattern becomes clearer. You don’t need to perform advanced statistical analysis to see the correlation between high poverty levels and low median incomes. Just filter to the highest levels of poverty and you’ll see clusters emerge in lower income places. The averages of the clusters are similarly much lower. Also, other than a few outliers, you won’t find many counties in the higher income regions.

These insights may not surprise you, but the point is that the clustered, averaged map helps show the trends visually. Though this example uses publicly-available data, imagine if it was sales prospects or other data specific to your business. By including all the data at whatever granularity you have available, BatchGeo can then bring out insights at a regional level using clustering, grouping and averages.

It’s been 34 years since John Hinckley attempted to assassinate Ronald Reagan, then less than three months into his presidency. Outside the Washington, D.C., Hilton Hotel on March 30, 1981, Hinckley fired six shots in less than two seconds. Reagan was injured on a ricochet, but Secretary of State James Brady and two others were hit directly. While this story is well known in the United States, other assassination attempts before and after it are not as common knowledge. The map below shows 18 acts, four of which ended in the death of a president.

View US President Assassination Attempts in a full screen map

The assassinations of Abraham Lincoln and John F. Kennedy are much researched and discussed. The other two are lesser known. James Garfield was shot while at the Washington, D.C., train station on his way to a vacation. Garfield was shot in the shoulder and back, living 11 weeks afterward.

William McKinley was attending a World’s Fair in Buffalo, New York, when he was shot by an anarchist. Unlike Lincoln or Garfield, McKinley had Secret Service detail. In fact, because of the public nature of the visit to the fair, the president had three rather than the usual single bodyguard. Wounded in the abdomen, McKinley died just over a week later.

McKinley was succeeded by Theodore Roosevelt, who would survive his own assassination attempt. While running for an unprecedented third term, Roosevelt was shot in the chest before a campaign stop in Milwaukee. The bullet first hit his glasses case and his 50-page speech, then lodged in his ribcage. Undeterred, Roosevelt gave a 90 minute speech to the crowd, but came in a distant second in the polls a month later.

A whopping 11 of the assassination attempts happened in D.C., including at the White House itself. The most recent, in 2011, involved a man shooting at the presidential home. Someone had the same idea in 1994, with President Clinton safely inside.

While there have been several international plots, there has only been one serious attempt outside of the US. In 2005, a Georgian threw a live grenade toward the podium during George W. Bush’s speech in Georgia (the country). It did not detonate, though the pin was pulled.

Other attempts include Gerald Ford in California (twice in one month) and President-elect Franklin Roosevelt in Miami. For more, peruse the map icons. Look out for icons that represent more than one assassination attempt, with their contents pageable.

In many areas of the United States it’s spring break. For many, that means heading to the airport for what is still the public’s fastest form of transportation. No matter whether you’re headed to sunny climes or on a business trip, if you have a connection to make, you have a high likelihood of passing through one of these airports. The 30 busiest in the world are mapped below, explorable by total passengers and country.

View World’s Busiest Airports in a full screen map

A full 40% of these busiest airports are in the United States. Many of these top airports are major hubs for major airlines, leading to a lot of traffic. Delta pioneered the hub and spoke system in the 1950s with what is still its main base of operations in Atlanta. It is still the busiest airport in the world.

Los Angeles’ LAX is the hub for multiple airlines and is popular for international destinations. Both United and American Airlines use Chicago O’Hare as a hub. Dallas, the fourth-largest US airport (and ninth overall), is also American’s home base.

Other US airports in the top 20 include Denver (#17) and New York’s JFK (#18).

Outside of the US, China has the most airports in the top 30, with four. Beijing is the second-busiest overall, and Hong Kong rounds out the top 10. Germany is the only other country with multiple airports on the list: Frankfurt (#11) and Munich (#30).

Only three continents are represented by the 30 busiest airports: North America has 12 of them, Asia has 11, and seven are in Europe. Soekarno-Hatta International Airport in Indonesia is the only airport in the southern hemisphere to make the list of busiest airports.

Air travel continues to grow, overall and at most of these top airports. Istanbul (#12) has seen an 11% increase in travelers over the last year. Seoul (#24) and Shanghai (#19) have increased by 9.7% and 7.6% respectively.

As you plan your travel, either now or in the future, consider these top airports as you put together your itineraries.