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 · 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
Open the chart and its numbersChart 3 of 3 · World
How has the world's population grown since 1960?
The interactive chart needs JavaScript. The numbers are on the chart's page.
The world had 8.22 billion people in 2025, about 2.7 times the 3.02 billion of 1960. It passed 8 billion in 2023. Figures are mid-year estimates from the United Nations, which revises them as new censuses come in.
How to read this chart
Each point is the number of people alive in the world in the middle of that year, estimated by the United Nations. The axis starts at zero, so the height of the line shows the true size. Look at how steep the line is to see how fast the population grew.
Questions to discuss
- Judging from the chart, about how many years did it take the world to add its most recent billion people?
- Is the line getting steeper or flatter in recent years? What does that tell you about the growth rate?
- These numbers are estimates that the UN revises. Why is it hard to count every person on Earth?
Source: World Bank, World Development Indicators: Population, total (CC BY 4.0 (credit the World Bank)) · Data as of Dec 31, 2025
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