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 · Health
How does heart disease compare with cancer as a cause of death in the US?
The interactive chart needs JavaScript. The numbers are on the chart's page.
In 1950 there were about 3 heart disease deaths for every cancer death in the US. By 2018 there were 1.1, because the heart disease death rate fell much faster than the cancer rate; around 2012 the two came within a few percent of each other. Heart disease had the higher rate in every year from 1900 to 2018. The ratio compares age-adjusted death rates from one CDC dataset, which stops at 2018.
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: CDC National Center for Health Statistics, Age-adjusted death rates for selected major causes of death (Public domain (U.S. government work)) · Data as of Dec 31, 2018
Open the chart and its numbersChart 2 of 2 · Energy
Where does US electricity come from?
The interactive chart needs JavaScript. The numbers are on the chart's page.
In 2025 natural gas made 40.8% of US electricity, followed by nuclear (17.7%) and coal (16.6%). Wind made 10.5% and solar 6.7%. Solar counts only utility-scale plants, not rooftop panels, and the 2025 figures are preliminary.
How to read this chart
Each bar is one energy source's share of all the electricity made in the U.S. in a year, so the bars add up to about 100%. The bars start at zero, so a bar twice as long means twice the share. Solar counts only large power plants, not panels on rooftops.
Questions to discuss
- Which source makes the most electricity? About how many times more than the smallest bar?
- Which of these sources burn fuel and which don't? What share of electricity comes from each group?
- Why might a chart of this kind look different in your state than for the whole country?
Source: U.S. Energy Information Administration, Monthly Energy Review (Table 7.2a) (Public domain (U.S. government work)) · Data as of Dec 31, 2025
Open the chart and its numbersTeachers: make your own chart assignment, or change this one. Free, no account needed.