Chart assignment
Charts to read and discuss
Read each chart, then answer its questions. Every chart shows its source and date; open it for a table of the numbers and the data to download.
Chart 1 of 3 · Earthquakes
How much rarer is each step up in earthquake magnitude?
The interactive chart needs JavaScript. The numbers are on the chart's page.
In 2025 the world recorded 6,428 earthquakes of magnitude 4.5 to 4.9, 1,983 of magnitude 5, 129 of magnitude 6, 15 of magnitude 7 and 1 of magnitude 8 or more. Each step up in magnitude is roughly ten times rarer, and releases about 32 times more energy. Countless smaller quakes go unrecorded worldwide, so the chart starts at 4.5.
How to read this chart
Each bar counts the earthquakes recorded worldwide in one year within a range of magnitudes. The bars start at zero. Each whole step up in magnitude releases about 32 times more energy, so a magnitude 7 quake is far more than one step stronger than a 6.
Questions to discuss
- Roughly how many times more common is each band than the one above it?
- The biggest bars are hard to compare with the smallest ones on this scale. What other way could you show these numbers?
- The chart starts at magnitude 4.5. Why might smaller earthquakes around the world go uncounted?
Source: U.S. Geological Survey, ANSS Comprehensive Earthquake Catalog (ComCat) (Public domain (U.S. government work); source U.S. Geological Survey) · Data as of Dec 31, 2025
Open the chart and its numbersChart 2 of 3 · Crime
Which big U.S. cities have the highest murder rates?
The interactive chart needs JavaScript. The numbers are on the chart's page.
In 2025 St. Louis, MO had the highest murder rate of the 89 biggest U.S. cities whose police reported a full year to the FBI, about 51.3 per 100,000 people, followed by Memphis, TN (31.0) and Cleveland, OH (28.0). Irvine, CA (0.0) and Plano, TX (0.7) had the lowest; the U.S. rate was about 4.4. Departments that didn't report a full year are left out (for 2025, New Orleans, Orlando and St. Petersburg, Florida). Each rate is per person the department serves, and a few, such as Las Vegas, Honolulu, Jacksonville and Louisville, serve their whole county. A city's rate also depends on where its borders fall, so compare cities with care.
How to read this chart
Each bar is the number of murders in a city in one year for every 100,000 people its police department serves. The dashed line is the U.S. rate. Murders are rare, so in a smaller city a handful more or fewer in one year can move its rate and its rank a lot.
Questions to discuss
- How many cities on the chart have a murder rate above the U.S. rate, and how many are below it?
- Why does a chart like this use murders per 100,000 people instead of the total number of murders in each city?
- A city's rank can jump from one year to the next. Why might small numbers make rates bounce around?
Source: FBI Crime Data Explorer, Uniform Crime Reporting Program (Public domain (U.S. government work); source FBI Uniform Crime Reporting Program) · Data as of Dec 31, 2025
Open the chart and its numbersChart 3 of 3 · World
What share of people use the internet in each country?
The interactive chart needs JavaScript. The numbers are on the chart's page.
In 2024, 94.7% of people in the United States used the internet and 64.9% in India. The highest share was 100%, and the lowest 8.6%, in Burundi. 182 countries and territories had a 2024 figure. It counts people who used the internet at least once in the previous three months; places without a 2024 figure are left out.
How to read this chart
Each bar is the share of a country's people who used the internet in the previous three months. The dashed line is the whole world. The chart opens on the top and bottom of the ranking; search for a country to find its bar among the rest.
Questions to discuss
- Find the United States and one country on another continent. How far apart are their shares?
- What do the countries at the bottom of the ranking have in common? What might keep people there offline?
- The world figure is closer to the bottom than many rich countries are to the top. Why might that be?
Source: World Bank, World Development Indicators: Individuals using the Internet (% of population) (CC BY 4.0 (credit the World Bank)) · Data as of Dec 31, 2024
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