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 2 · College football
How many college football games are decided by one score?
The interactive chart needs JavaScript. The numbers are on the chart's page.
36.6% of regular-season games between two FBS (top-division) teams in 2025 were decided by 8 points or fewer, what a touchdown and a two-point conversion can make up. About one game in three has been that close in most seasons since the 1940s; the closest seasons were the low-scoring 1930s, peaking at 49.4% in 1937. Ties count as close games. The chart starts in 1900; CollegeFootballData.com's records before then cover only a few dozen such games a season.
Questions to discuss
- In one sentence of your own, what does this chart show?
- Find the biggest change or difference in the chart. What might explain it?
- Who collected these numbers, and how recent are they? What else would you want to know before drawing a conclusion?
Source: CollegeFootballData.com, college football games (CollegeFootballData.com terms of use (factual data, credited to CollegeFootballData.com)) · Data as of Jan 20, 2026
Open the chart and its numbersChart 2 of 2 · 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
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