Those are econ placements, the finance program is separate and has even better placements. The median was definitely not Iowa, that is easily in the lower quintile. Here's a rough list of top placements, the median placement is about top 20 Harvard, Booth, Northwestern (x2), Penn, Minnesota, Michigan, Stanford, Cornell, UBC.
Michigan also has high attrition rates, right? Booth has very low attrition rates. I don't see why someone would want to be in an econ dept rather than a bschool. Basically the same job, just more money at the bschool.
I agree that Michigan is great in public finance, but the OP might change what he wants to do. I think if he goes to Booth he is way more likely to have access to better faculty, will have more security, get a better placements, and make more money than if he goes to Michigan. Ann Arbor is a really nice place to live though, and the dept is still quite good. These are both good options but I think that Booth clearly dominates.