Six teenagers drowned after slipping from a wading area into the deep water of a Louisiana river on Tuesday. None of the victims could swim, nor could the adult bystanders who watched helplessly as the children went under. What percentage of Americans can’t swim?

Somewhere between one-third and around one-half. In a 1994 CDC study, 37 percent of American adults said they couldn’t swim 24 yards, the length of a typical gymnasium lap pool. A 2008 study conducted by researchers at the University of Memphis found that almost 54 percent of children between 12 and 18 can do no more than splash around the shallow end of a pool. The difference between the two studies is somewhat surprising, as the CDC study suggested that children tend to be better swimmers than adults.

The Memphis study broke the data down demographically. White children were the most likely to self-report (or have their parents report) strong swimming skills, with 58 percent of those between the ages of 4 and 18 claiming the ability to traverse more than a pool length. Hawaiians and Pacific Islanders came in a close second at 55 percent. Forty-two percent of Hispanic and Latino children are strong swimmers. Asian-American and Native American children came in at 34 percent and 32 percent, respectively. African-Americans reported the fewest strong swimmers at 31 percent. Accident rates largely conform to these data. Black children between 5 and 14 years old are more than three times as likely to drown as their white peers. The six children who died in Louisiana were African-American.

A child’s ability to swim is also strongly correlated with his parents’ income. Sixty-seven percent of poor swimmers have a household income less than $49,999. Only 29 percent of skilled swimmers fall below that income level. In the second phase of the University of Memphis study, researchers looked more closely at income and found that 12 percent of children who participate in a reduced-cost school lunch program—an easier piece of data for a child to report than household income—said they don’t even feel comfortable in the shallow end of a pool, compared with just 6 percent of wealthier children.

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Explainer thanks Carol C. Irwin of the University of Memphis.

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