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Answer key · for teachers
Figures as of November 12, 2026, from each chart's current data.
Chart 1 of 3 · Food and drug safety
The chart's answer: The FDA classified 190 food recalls in 2025 for an allergen left off the label, such as milk, peanuts, tree nuts, wheat, soy, eggs, fish, shellfish or sesame; the most since 2013 was 282 in 2017. From 2013 through 2025, undeclared allergens were the most common reason food was recalled. A recall counts once however many products it covers, in the year FDA first listed it in its weekly Enforcement Report. Chartly sorted FDA's written reasons by their key words; a recall for a germ as well counts under the germ. Meat, poultry and most egg products are USDA's to recall and aren't included. The newest allergen recalls, this year's included, are listed below.
In one sentence of your own, what does this chart show?
Open question: answers will vary. Look for answers that use the chart's numbers and source.
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. Food and Drug Administration, Enforcement Reports (openFDA food recall data) (Public domain (U.S. government work); source U.S. Food and Drug Administration, openFDA) · Data as of Nov 4, 2026 · chart.ly/charts/food-allergen-recalls-per-year
Chart 2 of 3 · World
The chart's answer: 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.
Judging from the chart, about how many years did it take the world to add its most recent billion people?
Is the line getting steeper or flatter in recent years? What does that tell you about the growth rate?
These numbers are estimates that the UN revises. Why is it hard to count every person on Earth?
Open question: answers will vary. Look for answers that use the chart's numbers and source.
Source: World Bank, World Development Indicators: Population, total (CC BY 4.0 (credit the World Bank)) · Data as of Dec 31, 2025 · chart.ly/charts/world-population
Chart 3 of 3 · Climate
The chart's answer: The contiguous US averaged 54.6°F in 2025. The warmest year since records began in 1895 was 2024, at 55.5°F. Through 2025, the dashed trend line, the straight line that best fits every year, rose about 0.18°F a decade, or 2.3°F since 1895, and warming had sped up to about 0.5°F a decade since 1970. Alaska and Hawaii aren't included.
Find the warmest and coolest years on the chart. How many degrees apart are they?
Why might one year be much cooler than the year before, even while the trend line keeps rising?
The axis doesn't start at zero here, but bar charts always do. Why is that fair for temperatures but not for bars?
Source: NOAA National Centers for Environmental Information, Climate at a Glance (Public domain (U.S. government work)) · Data as of Dec 31, 2025 · chart.ly/charts/us-average-temperature
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