What about differences within nonprofit sectors?

in reference to: Amaze Your Friends with these Nonprofit Factoids | Blue Avocado (view on Google Sidewiki)

I'd like to see these figures broken out by sectors within the 501 (c)3 category, as well. If, as you mention below, you take out the hospitals and universities, I believe the differences would increase even more dramatically.

Why? The impact of unionization and/or more men working in hospitals and and universities?

Thanks, Rick Cohen at Blue Avocado, for pulling together the data.