The Opportunity Atlas is a great resource for anyone interested in studying inter-generational economic mobility across the United States. Using anonymized tax and census records, the data follows more than 20 million children born between 1978 and 1983 from the census tract where they grew up to their adult incomes in their mid-thirties. Here we focus on the outcomes of children from Cook County.
For each census tract, the data reports the average adult income percentile reached by children whose parents stood at the 25th percentile (poor families, but not the poorest). This measure of economic mobility is also provided by race and gender.
First, we map the variation in economic mobility across Cook County for all children. The color scale goes from red to blue, so bluer tracts lift poor children higher than redder ones. I was surprised and saddened to see that my neighborhood of Hyde Park was in the redder hues.
Because the Atlas reports outcomes separately by race, we can ask a deeper question: within the same census tract, do Black and White children from equally poor families (parents at the 25th percentile) earn similar incomes on average in adulthood? Each dot below is one of 729 Cook County tracts where the Atlas had data on both groups. If the neighborhood offered both groups the same opportunity, the dots would crowd the diagonal.
In 90.8% of Cook County tracts, the White child grew up to out-earn the Black child from a family of comparable income — by about 11 percentiles on average.
Use the dropdown to spotlight one neighborhood across all three charts below.
Next, we plot the same comparison for outcomes in girls versus boys. Among girls, the White child achieves higher income in 88.7% of tracts; for boys, the number is 92.5%.
The scatter plots above show that the racial gap exists; the map below shows where it is higher and lower. Each tract is shaded by the difference between White and Black children's mean adult rank — darker red indicates where White children earn more; darker blue indicates where Black children earn more. Gray areas represent tracts where data is insufficient.