What a Childhood in San Juan County Does to Future Income

Location matters – enormously. If you’re poor and live in Washington, it’s better to be in Whitman County than in Grays Harbor County orCowlitz County. Not only that, the younger you are when you move to Whitman, the better you will do on average. Children who move at earlier ages are less likely to become single parents, more likely to go to college and more likely to earn more.

Every year a poor child spends in Whitman County adds about $210 to his or her annual household income at age 26, compared with a childhood spent in the average American county. Over the course of a full childhood, which is up to age 20 for the purposes of this analysis, the difference adds up to about $4,100, or 16 percent, more in average income as a young adult.

These findings, particularly those that show how much each additional year matters, are from a new study by Raj Chetty and Nathaniel Hendren that has huge consequences on how we think about poverty and mobility in the United States. The pair, economists at Harvard, have long been known for their work on income mobility, but the latest findings go further. Now, the researchers are no longer confined to talking about which counties merely correlate well with income mobility; new data suggests some places actually cause it.

Consider San Juan County, Wash., the focus of this article. It’s below average in helping poor children up the income ladder. It ranks 980th out of 2,478 counties, better than about 40 percent of counties. It is relatively worse for poor girls than it is for poor boys.

Here are the estimates for how much 20 years of childhood in San Juan County adds or takes away from a child’s income (compared with an average county), along with the national percentile ranking for each.