I think both Detroit and Wayne County [[the city more dramatically) are on the verge of the point at which inflow exceeds outflow. 2 reasons for this. 1) Continued rapid growth in downtown & nearby neighborhoods [[slowing creeping outward), 2) Most of those trying to "get out" have already done so. Downtown boom will continue and spread outward. Outer neighborhoods are slowly stabilizing and will mostly also grow in the next decade, although most won't boom. 2020 will have only slightly less than 2010, and 2030 will be quite a bit more. I second the notion that mid-decade numbers are not precise. Of course, so are the actual Census numbers every 10 years.