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 much US debt does the Federal Reserve own?
  2. How much rarer is each step up in earthquake magnitude?

Chart 1 of 2 · Federal budget

How much US debt does the Federal Reserve own?

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

The Federal Reserve held $4.58 trillion of Treasury securities on October 28, 2026, compared with a peak of $5.77 trillion in May 2022. Its holdings jumped when it bought Treasuries to support the economy after the 2008 financial crisis and in the 2020 pandemic, when they more than doubled in two years, and fell as it let them run off from 2022. Each point is the last weekly figure of the month, including TIPS' inflation adjustment.

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: Federal Reserve Bank of New York, System Open Market Account (SOMA) Holdings (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 Oct 28, 2026

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Chart 2 of 2 · Earthquakes

How much rarer is each step up in earthquake magnitude?

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

In 2025 the world recorded 6,428 earthquakes of magnitude 4.5 to 4.9, 1,983 of magnitude 5, 129 of magnitude 6, 15 of magnitude 7 and 1 of magnitude 8 or more. Each step up in magnitude is roughly ten times rarer, and releases about 32 times more energy. Countless smaller quakes go unrecorded worldwide, so the chart starts at 4.5.

How to read this chart

Each bar counts the earthquakes recorded worldwide in one year within a range of magnitudes. The bars start at zero. Each whole step up in magnitude releases about 32 times more energy, so a magnitude 7 quake is far more than one step stronger than a 6.

Questions to discuss

  1. Roughly how many times more common is each band than the one above it?
  2. The biggest bars are hard to compare with the smallest ones on this scale. What other way could you show these numbers?
  3. The chart starts at magnitude 4.5. Why might smaller earthquakes around the world go uncounted?

Source: U.S. Geological Survey, ANSS Comprehensive Earthquake Catalog (ComCat) (Public domain (U.S. government work); source U.S. Geological Survey) · Data as of Dec 31, 2025

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