IMO the biggest advantage of private schools is that they do not have the riff raff that public schools do that count towards their enrollment, but contribute little towards anything extra curricular.

That is unless you consider smoking extra curricular.

Most kids at private/parochial schools come from supportive homes and want to and are expected to be a productive part of the system. 10-15% of their enrollment is not transient, completing less than even one school year.

If you removed all of those kids from our district, there is absolutely no doubt that we would lower at least one classification. That is why a multiplier makes sense to me.