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 2 · Income tax
What average income tax rate does each income group pay?
The interactive chart needs JavaScript. The numbers are on the chart's page.
In tax year 2023, the 0.1% of tax returns with the highest incomes paid 26.7% of their adjusted gross income in federal income tax, on average. The rate was 25.9% for the rest of the top 1%, 16.8% for the next 9%, 10.6% for the next 15%, 7.7% for the next 25% and 3.7% for the bottom half. The average rate is total income tax divided by total income for each group, which is lower than the top bracket rate (37%) because lower rates apply to the first dollars of income and to long-term capital gains and most dividends. It counts income tax after credits, never below zero, and leaves out payroll taxes for Social Security and Medicare, which weigh more on lower and middle incomes, as well as returns of people claimed as dependents.
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: IRS Statistics of Income, Table 4.1 (individual returns by income percentile) (Public domain (U.S. government work)) · Data as of Dec 31, 2023
Open the chart and its numbersChart 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
- Roughly how many times more common is each band than the one above it?
- The biggest bars are hard to compare with the smallest ones on this scale. What other way could you show these numbers?
- 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
Open the chart and its numbersTeachers: make your own chart assignment, or change this one. Free, no account needed.