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. What is the average income on tax returns in your ZIP code?
  2. Are U.S. roads getting safer per mile driven?

Chart 1 of 2 · Income tax

What is the average income on tax returns in your ZIP code?

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

Type any ZIP code to see the average income on the tax returns filed from it in tax year 2023, next to its state's and the U.S. average of $96,717. ZIP code 20001 in Washington, D.C., shown first, averaged $126,264. In tax year 2022, across the 27,588 ZIP codes in the data, half averaged less than about $68,300, and the highest was Fisher Island, Florida (33109), at $4.4 million on 400 returns. Income here is adjusted gross income, the income on a tax return after a few adjustments; an average can be pulled far up by a few very large incomes, and one return can cover a married couple. The IRS leaves out ZIP codes with fewer than 100 returns, single buildings and nonresidential ZIP codes, and returns with negative income. Tax year 2023 is the newest year the IRS has published by ZIP 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?

Source: IRS Statistics of Income, individual income tax ZIP code data (Public domain (U.S. government work)) · Data as of Dec 31, 2023

Open the chart and its numbers

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.