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 · Air travel
What causes most flight delays?
The interactive chart needs JavaScript. The numbers are on the chart's page.
In the 12 months through August 2026, 39.8% of all minutes of delay came from a late-arriving aircraft: a plane that left its last airport late. The airline itself (crew, maintenance, cleaning, fueling) caused 32.9%, the air traffic system 21.1% and severe weather 6%. Weather also hides in the other causes: BTS counts ordinary weather that slows traffic under the air traffic system.
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: U.S. Bureau of Transportation Statistics, Airline On-Time Performance (Reporting Carrier On-Time Performance, 1987–present) (Public domain (U.S. government work)) · Data as of Aug 31, 2026
Open the chart and its numbersChart 2 of 2 · World
How much does each country spend on health care per person?
The interactive chart needs JavaScript. The numbers are on the chart's page.
In 2023, the United States spent $13,473 per person on health care, about 10 times the world figure of $1,317. Germany spent $6,395, Japan $3,638, China $763 and India $85; Madagascar spent the least, $17. Search 191 countries and territories. Spending counts what governments, insurers and households paid for health care, but not new hospitals or equipment, in US dollars at each year's exchange rates, not adjusted for differences in prices.
How to read this chart
Each bar is what a country spent on health care in a year, by governments, insurers and households together, divided by its population and turned into U.S. dollars. The dashed line is the world. The figures aren't adjusted for prices, so a dollar buys more care in some countries than others.
Questions to discuss
- About how many times the world figure does the United States spend per person?
- Does spending more on health care per person always mean people live longer? What other chart on Chartly could help you check?
- Doctors and nurses are paid less in some countries. How would that change what these dollar figures can tell you?
Source: World Bank, World Development Indicators: Current health expenditure per capita (current US$) (CC BY 4.0 (credit the World Bank)) · Data as of Dec 31, 2023
Open the chart and its numbersTeachers: make your own chart assignment, or change this one. Free, no account needed.