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. Who owns the US national debt?
  2. How much has the US warmed since 1895?
  3. How fast has the world come online?

Chart 1 of 3 · Federal budget

Who owns the US national debt?

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

At the end of August 2026 the federal debt was $40.2 trillion. Other U.S. investors (banks, mutual funds, pension funds, state and local governments and people) held $18.5 trillion, 46%. Foreign investors held $9.33 trillion (23%), federal trust funds such as Social Security's held $7.76 trillion (19%), and the Federal Reserve $4.55 trillion (11%). Foreign holdings are Treasury's TIC estimate, partly at market value, and the U.S. share is what's left after the others, so the split is approximate.

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: U.S. Treasury Fiscal Data, Debt to the Penny; U.S. Treasury, TIC Major Foreign Holders of Treasury Securities; Federal Reserve Bank of New York, SOMA Holdings (Treasury data public domain (U.S. government work). The SOMA Holdings data is subject to the Terms of Use posted at newyorkfed.org; the New York Fed is not responsible for publication.) · Data as of Aug 31, 2026

Open the chart and its numbers

Chart 2 of 3 · Climate

How much has the US warmed since 1895?

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

The contiguous US averaged 54.6°F in 2025. The warmest year since records began in 1895 was 2024, at 55.5°F. Through 2025, the dashed trend line, the straight line that best fits every year, rose about 0.18°F a decade, or 2.3°F since 1895, and warming had sped up to about 0.5°F a decade since 1970. Alaska and Hawaii aren't included.

How to read this chart

Each point is one year's average temperature across the lower 48 states, in degrees Fahrenheit. The axis doesn't start at zero, so a small rise looks steep: read the numbers on the axis, not the height of the line. The dashed line is the trend, the straight line that best fits every year; single years bounce above and below it.

Questions to discuss

  1. Find the warmest and coolest years on the chart. How many degrees apart are they?
  2. Why might one year be much cooler than the year before, even while the trend line keeps rising?
  3. The axis doesn't start at zero here, but bar charts always do. Why is that fair for temperatures but not for bars?

Source: NOAA National Centers for Environmental Information, Climate at a Glance (Public domain (U.S. government work)) · Data as of Dec 31, 2025

Open the chart and its numbers

Chart 3 of 3 · World

How fast has the world come online?

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

73.6% of the world's people used the internet in 2025, up from 15.6% in 2005, the first year the World Bank gives a world figure. It counts people who used the internet at least once in the previous three months. The world figures are estimates by the International Telecommunication Union.

How to read this chart

Each point is the share of the world's people who used the internet at least once in the previous three months, as estimated by the International Telecommunication Union. The axis starts at zero, so the height shows the true share. The steeper the line, the faster people were coming online.

Questions to discuss

  1. About what share of the world was online in the first year on the chart, and in the latest year?
  2. Did the share grow faster in some years than others? What could have sped it up?
  3. Using the internet once in three months counts here. What does this number leave out about how people get online?

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