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. Which US airports have the most delayed departures?
  2. Are U.S. roads getting safer per mile driven?

Chart 1 of 2 · Air travel

Which US airports have the most delayed departures?

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

In the 12 months through August 2026, 32.3% of flights leaving Dallas, TX (DAL) left 15 or more minutes late, the most of the 102 U.S. airports with at least 10,000 departures. Kona, HI (KOA) had the fewest, 13.7%; Atlanta (ATL), the busiest, was at 21.8%. Search for any airport by city or code.

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?

Chart 2 of 2 · 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?

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