Chris, yeah, that info is helpful, but it doesn't tell you everything. Two reasons:
1) Some organizations have higher overhead within the nature of their operations than others do. An obvious example is the Red Cross. The expensive part of their business is getting to where shit is going down, not the actual supplies and such. That takes a lot of logistical expertise.
You can compare NGO's with similar missions, operations, and locations, though.
2) I am using an example the first scam nonprofit I found, as a project for my government and nonprofit accounting class. It was an animal rescue that I can't name because I could get sued. On paper they were excellent. 87% of their expenses went to operations.
In reality, they were using their nonprofit status to build additions to their home, a swimming pool, etc. and their nonprofit was only there to support a for-profit business, which looked like part of the nonprofit but wasn't.
They were also breeding dogs. Huge no-no in animal rescue.