"That recalculation ... saw about a third of schools go up in decile, a third go down, and the rest were unchanged," he said.
"That's very similar to what happened when it was done in 2007."
He said the ministry knows primary schools with small rolls are more susceptible to changes in their community.
"It's also important for schools to understand that we recognise that circumstances can continue to change. There's another review opportunity later this year if any school is in that situation as well as further annual reviews."
Dr Stoop says the 85 schools to receive additional funding because of the lowering of their decile rating have not been disadvantaged because their increased funding will be backdated.
"For schools whose deciles went up as part of last year's decile review the Government has made around $8 million in transitional funding available over 18 months to help them adjust to new funding levels."