Interactive: Do you look like America?

By Chris Wilson

Every few years, the Census Bureau releases its projections for how many people of every possible combination of age, sex, race and ethnicity will live in the United States over the next half century. Curious how many 35-year-old female Hispanic American Indian/Alaskan Natives there will be in 2045? I can tell you.It’s 17,632.

One might scoff at this sort of datum. How could the Census Bureau possibly know what medical advances will prolong our lives over the next 33 years? Or what geopolitical currents will shift immigration patterns? And what about the robot apocalypse? Will the robots prey on every age group with statistical uniformity?

The Census Bureau doesn’t know, of course. A projection is a portrait of what the country will look like if present trends persist exactly as they are now: if babies are born to parents of different races at the same rates, immigration is unchanged and people’s life spans adhere precisely to the unforgiving mathematics of decline. No one, including census demographers, believes this will happen.

When your mother says, “Keep eating like that and you'll have a heart attack when you’re 50,” she is not predicting the future. She is commenting on your present behavior. Population projections have the same effect: They don’t tell us much about the distant future, but they tell us a surprising amount about the present.

“The idea is that if all of the assumptions were to come true, that is what we would expect the population to be at that future point in time,” says census demographer Jennifer Ortman, who led the team that produced the projections.

In the interactive below, you can track the predicted population for any demographic profile, based on the figures released last month. Each line represents people born in a single year. You can drag the sliding bar back and forth to examine individual years of birth.

If the line rises, it is due to immigration (there is no method by which people of a given age otherwise materialize from thin air). Lines tend to tick up at the end because the census groups everyone who is 100or older together, and there tend to be more of them than there are 99-year-olds.

If this view is too morbid for you—I’d like to think I have more than a 3-in-4shot at being a vibrant, dashing 77-year-old in 2060—you can switch the view in the upper right-hand corner to “by age,” which shows a different view: How many people of an exact age, race, ethnicity and sex will live in America in the next five decades? Rather than, for example, track people who are 37 right now,this tracks the number of 37-year-olds there will be each year going forward.

I find this more interesting, because it shows us waves of births and captures the rise or decline of a given slice of the population independent of time's cruel recall. There will be twice as many 72-year-olds in 2060 as there are today, for example—a fact that starkly captures the reality of our aging population. Dragging the bar to age zero shows projected births. Dragging it to65 shows us that, in the next several years alone, the number of newly eligible retirees will spike dramatically.

When we look at these projections, we’re visited by the Ghost of Census Future—not, perhaps, attended by the same terror as Scrooge encountered, but with the same knowledge that what we’re really seeing is the present.