Principal on his school's $70,000 loss in decile changes

With the release of new decile ratings which determine funding for schools, is there a better way to work out funding formulas so disadvantaged students don't miss out? Dave Appleyard is the principal of Rata Street School in Naenae which has gone from a decile 1 to a decile 2 ranking in the new calculations; with the loss of $70 000.