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.

  1. How many major earthquakes happen each year?
  2. Are U.S. roads getting safer per mile driven?

Chart 1 of 2 · Earthquakes

How many major earthquakes happen each year?

The interactive chart needs JavaScript. The numbers are on the chart's page.

The world had 16 earthquakes of magnitude 7 or more in 2025. Since 1900 the yearly count has ranged from 4 in 1930 to 24 in 2010, with no lasting rise. Quakes this strong are recorded wherever they strike, so even early counts are fairly complete; magnitudes before the 1960s are scientists' later estimates from old seismograms.

Questions to discuss

  1. In one sentence of your own, what does this chart show?
  2. Find the biggest change or difference in the chart. What might explain it?
  3. Who collected these numbers, and how recent are they? What else would you want to know before drawing a conclusion?

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 numbers

Chart 2 of 2 · Road safety

Are U.S. roads getting safer per mile driven?

The interactive chart needs JavaScript. The numbers are on the chart's page.

In 2024 there were 1.19 deaths for every 100 million miles driven, down from 3.35 in 1980. The lowest rate was 1.08 in 2014; it jumped to 1.34 in 2020, when people drove less but deaths rose. Miles driven are the Federal Highway Administration's estimates.

How to read this chart

Each point is the number of people killed in traffic crashes for every 100 million miles Americans drove that year. Dividing by miles driven turns a count into a rate, so years when people drove more or less can be compared fairly.

Questions to discuss

  1. About what fraction of the 1980 rate is the rate in the latest year?
  2. In 2020 people drove less, but the rate went up. What could explain that?
  3. Why is deaths per mile a fairer way to compare years than the total number of deaths?

Source: NHTSA Fatality Analysis Reporting System (FARS) and FHWA Highway Statistics (table VM-2) (Public domain (U.S. government work)) · Data as of Dec 31, 2024

Open the chart and its numbers

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