Chicago and Milwaukee have historically shared twin fates economically. When employment is up in one place, it’s typically up in the other. Not so, of late.

A new study by the Chicago Fed shows that Milwaukee has seen a considerable bounce in total employment while things have remained stagnant in Chicago.

The sudden divergence of employment trends says a lot about both towns. Had Chicago mirrored Milwaukee’s job growth, about 100,000 more people would be employed across the city. That should beg serious policy questions.

Milwaukee has benefited from a strong rebound in manufacturing. That industry is less densely located in Chicago–something else that begs policy questions.

Chicago has a heavier concentration of financial firms. The authors point out that Chicago could catch up to Milwaukee if manufacturing declines and financial services boom.