Laura Bliss is a staff writer at CityLab, covering transportation and technology. She also authors MapLab, a biweekly newsletter about maps (subscribe here). Her work has appeared in the New York Times, The Atlantic, Los Angeles magazine, and beyond.
Surprisingly, your chances of living to your next birthday don’t always decline as you age.
An aging population may be straining health care, social security, and city infrastructure. But it also means people live longer—including, hopefully, you. A new visualization from Flowing Data-meister Nathan Yau brings to life your odds of living one year to the next, with the charming metaphor of balls dropping off a downward curve.
Yau writes that he wanted to bring some nuance to solid, two-digit life expectancy averages. Yes, the average American woman can expect to live to age 81, and a man to 76. But the probability of living to our next birthday changes as we age, declining rapidly after we hit 60. Yau writes:
The graphic uses data from the Social Security Administration to simulate your possible lifetimes. That's plural. The line shows the probability you live to see your next birthday, given age and sex. Each running dot represents a possibility.
You can enter in your age and sex (there are only “male” and “female” options, since that’s what the SSA has data for) to see how your chances pan out.
For someone like me, a female in my twenties, most of the marbles drop pretty slowly, sliding along the flat plane of my 30s, 40s, and 50s before dropping off in my 60s, 70s, and 80s, when I have the highest odds of dying (whee!). If I watched long enough, I’d see some balls drop at younger ages, representing my slim odds (knock on wood!) of an early death.
If I change my entries to that of a man in his late 50s, the balls cascade much faster. Something interesting does happen if you’re 70 or older, though:
Life expectancy increases and the balls tend to drop farther past the overall life expectancy point. That is, as you shift into later years, life is like, “Hey, you're pretty good at this aging game. Better than most. You're probably going to live longer than the average person.”
As Yau points out, that suggests that the basic equations we use to calculate social security and retirement planning are a little more complicated than we might think. It’s one more marble to ponder as we start adapting society to the needs of a large, aging population.