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Answer key · for teachers

Charts to read and discuss

Figures as of November 12, 2026, from each chart's current data.

Chart 1 of 3 · Food and drug safety

How many food recalls are for undeclared allergens each year?

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.

Key numbers (Food recalls for undeclared allergens)

Questions

  1. 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.

  2. Find the biggest change or difference in the chart. What might explain it?

    • 2013 to 2025: up 36 (+23%)
    • Biggest rise from one point to the next: 40, 2022 to 2023
    • Biggest drop from one point to the next: 78, 2018 to 2019
  3. Who collected these numbers, and how recent are they? What else would you want to know before drawing a conclusion?

    • Newest: 190 in 2025
    • Source: U.S. Food and Drug Administration, Enforcement Reports (openFDA food recall data), data as of November 4, 2026

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 · Climate

How much has the US warmed since 1895?

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.

Key numbers (Average temperature, °F (contiguous U.S.))

Questions

  1. Find the warmest and coolest years on the chart. How many degrees apart are they?

    • Highest: 55.48 (2024)
    • Lowest: 50.05 (1917)
  2. Why might one year be much cooler than the year before, even while the trend line keeps rising?

    • 1895 to 2025: up 4.29 (+9%)
    • Biggest rise from one point to the next: 2.72, 1920 to 1921
  3. The axis doesn't start at zero here, but bar charts always do. Why is that fair for temperatures but not for bars?

    • First on the chart: 50.33 in 1895

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

Chart 3 of 3 · Health

How long do Americans live, and how has that changed since 1900?

The chart's answer: A baby born in the US in 2018 could expect to live 78.7 years, up from 47.3 in 1900. The sharpest drop was in 1918, to 39.1 years, during the influenza pandemic. This CDC dataset stops at 2018; later NCHS reports put life expectancy at 78.4 years in 2023 and 79.0 in 2024, after a fall during the COVID-19 pandemic.

Key numbers (Life expectancy at birth, years)

Questions

  1. Find the sharpest drop on the chart. What happened in the world that year?

    • 1900 to 2018: up 31.4 (+66%)
    • Biggest drop from one point to the next: 11.8, 1917 to 1918
  2. Life expectancy in 1900 was under 50. Does that mean most adults died in their 40s? What else could lower the average?

    • 1900: 47.3
  3. What changes in medicine, food or public health could explain the long rise?

    • 1900 to 2018: up 31.4 (+66%)
    • Biggest rise from one point to the next: 15.6, 1918 to 1919

Source: CDC National Center for Health Statistics, Death rates and life expectancy at birth (Public domain (U.S. government work)) · Data as of Dec 31, 2018 · chart.ly/charts/us-life-expectancy

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