Church Project Theorem: The Minority Report
There are a lot of conditions that influence the health of a parish, including attendance, leadership, finances, etc. Like it or not, though, one important issue is often the demographics of the surrounding areas.
It's a bit crude, I know, but it's pretty well established that predominantly minority neighborhoods tend to be worse off than more mixed or heterogeneous Caucasian areas. Urban parishes usually do worse in these areas, because they're usually struggling, impoverished communities. Not a knock against minorities, mind you, whose passion and dedication for these places is exemplary; they just have a tendency to be concentrated in the poorest areas.
Basically, any Fat Girl Principle parish.