All schools have a degree of a public good

Comments on Scott Prasser “Private schools a public good“ 22/12/2011, http://www.theaustralian.com.au/national-affairs/opinion/private-schools-a-public-good/story-e6frgd0x-1226227945644
While Prasser made a god point in terms of the differences in the share of public/non-public students when criticising the AEU's claim that the share of public school funding in Australia is lower than the OECD average, he, however, has not made a more comparable comparison along the line of the AEU's argument and that is a bit of pity in terms of information and the debate of education funding in Australia.
Presumably, it is possible to get a figure of government funding per student for public schools versus government funding per student for non-public schools. By using that ratio one can compare the relative funding of government for public school versus non-public schools with other countries.
One has to wonder why didn’t the professor present such figures?
Prasser argues that “The Gonski review is a lost opportunity to shift the school funding debate into an informed discussion of policies.”
Hasn’t he lost a good opportunity to inform the debate?

PS: a compromise deal could be that a  garranteed fixed proportion of funding per government student for non-government school student. If there is a need to make a difference between Catholic and private schools, then a higher proportion for the former could be more appropriate.