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 · Space
How many planets outside our solar system are discovered each year?
The interactive chart needs JavaScript. The numbers are on the chart's page.
Astronomers confirmed 246 new planets around other stars in 2025. The first were found in 1992, and the count leaped in 2014 and 2016 (872 and 1,504), when NASA's Kepler team confirmed hundreds of its candidates at once. The archive counts a planet in the year its discovery was published and keeps adding late confirmations, so recent years can still rise.
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: NASA Exoplanet Archive, Planetary Systems Composite Data (Public domain (NASA data); this research has made use of the NASA Exoplanet Archive, operated by Caltech under contract with NASA) · Data as of Dec 31, 2025
Open the chart and its numbersChart 2 of 3 · Inflation
How fast are US prices rising?
The interactive chart needs JavaScript. The numbers are on the chart's page.
The inflation rate was 3.7% in September 2026: how much consumer prices changed from the same month a year earlier. Each point makes that comparison, back to 1914, the first year BLS can compare. Inflation peaked at 23.7% in June 1920 and at 14.8% in March 1980; the 9.1% of June 2022 was the highest since 1981. Prices fell as fast as 15.8% a year in 1921 and 10.7% in 1932. BLS collected no prices in October 2025, during a lapse in federal funding, so that month and October 2026 are missing.
How to read this chart
Each point compares consumer prices in a month with the same month a year earlier. A value of 3 means things cost about 3% more than a year before; below zero means prices fell. The chart shows how fast prices change, not how high they are.
Questions to discuss
- Find two times when inflation was highest. What was happening in the country then?
- If inflation falls from 8% to 3%, are prices going down, or just rising more slowly?
- Find a stretch when the line is below zero. Why might falling prices be bad news for workers and businesses?
Source: U.S. Bureau of Labor Statistics, Consumer Price Index (CPI-U, all items) (Public domain (U.S. government work)) · Data as of Sep 30, 2026
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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