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. Where does US electricity come from?

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

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Chart 2 of 2 · Energy

Where does US electricity come from?

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

In 2025 natural gas made 40.8% of US electricity, followed by nuclear (17.7%) and coal (16.6%). Wind made 10.5% and solar 6.7%. Solar counts only utility-scale plants, not rooftop panels, and the 2025 figures are preliminary.

How to read this chart

Each bar is one energy source's share of all the electricity made in the U.S. in a year, so the bars add up to about 100%. The bars start at zero, so a bar twice as long means twice the share. Solar counts only large power plants, not panels on rooftops.

Questions to discuss

  1. Which source makes the most electricity? About how many times more than the smallest bar?
  2. Which of these sources burn fuel and which don't? What share of electricity comes from each group?
  3. Why might a chart of this kind look different in your state than for the whole country?

Source: U.S. Energy Information Administration, Monthly Energy Review (Table 7.2a) (Public domain (U.S. government work)) · Data as of Dec 31, 2025

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