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 does a dozen eggs cost in the US?
  2. Are U.S. roads getting safer per mile driven?
  3. How has the world's population grown since 1960?

Chart 1 of 3 · Inflation

How much does a dozen eggs cost in the US?

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

A dozen grade A large eggs averaged $2.27 in September 2026. The record so far is $6.23 in March 2025; prices spiked in 2023 and 2025 when bird flu cut the number of laying hens. Prices are BLS averages across US cities since 1980, when this series begins, in dollars of the day, not adjusted for inflation. October 2025 is missing because a lapse in federal funding stopped data collection.

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. Bureau of Labor Statistics, CPI Average Price Data (eggs, grade A, large) (Public domain (U.S. government work)) · Data as of Sep 30, 2026

Open the chart and its numbers

Chart 2 of 3 · Road safety

Are U.S. roads getting safer per mile driven?

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

In 2024 there were 1.19 deaths for every 100 million miles driven, down from 3.35 in 1980. The lowest rate was 1.08 in 2014; it jumped to 1.34 in 2020, when people drove less but deaths rose. Miles driven are the Federal Highway Administration's estimates.

How to read this chart

Each point is the number of people killed in traffic crashes for every 100 million miles Americans drove that year. Dividing by miles driven turns a count into a rate, so years when people drove more or less can be compared fairly.

Questions to discuss

  1. About what fraction of the 1980 rate is the rate in the latest year?
  2. In 2020 people drove less, but the rate went up. What could explain that?
  3. Why is deaths per mile a fairer way to compare years than the total number of deaths?

Chart 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

  1. Judging from the chart, about how many years did it take the world to add its most recent billion people?
  2. Is the line getting steeper or flatter in recent years? What does that tell you about the growth rate?
  3. 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

Open the chart and its numbers

Teachers: make your own chart assignment, or change this one. Free, no account needed.