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 often do ranked college football teams lose to unranked teams?
  2. How much carbon dioxide does each country emit per person?

Chart 1 of 2 · College football

How often do ranked college football teams lose to unranked teams?

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

Unranked FBS teams won 19.7% of their games against AP Top 25 teams in 2025. The share has ranged from 4.5% in 1998 to 25.9% in 2007, and has usually been higher since 2000 than in the 1990s. A team counts as ranked if it was in the AP poll that stood before the game; bowl games count, and games against lower-division (FCS) teams don't. The chart starts in 1989, when the AP poll began ranking 25 teams every week.

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: CollegeFootballData.com, college football games and AP Top 25 polls (CollegeFootballData.com terms of use (factual data, credited to CollegeFootballData.com)) · Data as of Jan 20, 2026

Open the chart and its numbers

Chart 2 of 2 · World

How much carbon dioxide does each country emit per person?

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

In 2024, people in the United States emitted 13.6 tonnes of carbon dioxide each, in China 9.3 and in India 2.2, against 4.7 worldwide. The highest figure was 82.8 tonnes in Palau, then Qatar (47.3) and Bahrain (23.9). Search 203 countries and territories. The figures count carbon dioxide from burning fuel, industry and other sources, but not from changes in land use such as cutting forests; in a small country, a few power plants, refineries or fuel sales spread over few people can make the figure very high.

How to read this chart

Each bar is the carbon dioxide a country put into the air in a year, divided by its population, in tonnes per person. The dashed line is the world. A country can emit a lot in total but little per person if it has many people, and a tiny country with a refinery or power plant can top the list.

Questions to discuss

  1. Compare the United States, China and India. Which emits the most per person, and is that the one that emits the most in total?
  2. Why might some small countries have the highest figures on the chart?
  3. Which seems fairer for comparing countries' share of the blame for climate change, total emissions or emissions per person? Why?

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