The reason was not just the difficulty of finding enough teachers willing to move to Auckland but of keeping those who were here.
Those saving for a house could buy one much sooner if they moved out of Auckland.
If they owned a modest house in Auckland it was tempting to sell up and buy something better in a smaller town for the same price. In three of the surveyed primary schools, there were no less than 28 vacancies at the start of this month to replace teachers who had resigned.
The highest turnover is in schools in Auckland's areas of highest wealth and half those who resigned had left the city.
The problem is not, of course, confined to education. All sorts of employers will be finding Auckland house prices a deterrent to recruitment. But many probably already pay a premium to attract staff they need.
In the state sector it is not so easy. Pay scales are set nationally in negotiations with unions that prefer to raise all rates across the country. And it bargains with the Education Ministry, which is not convinced an Auckland margin is needed.
But teachers have a starting salary of $48,000 and the top of the scale is $78,000. They are hard put to save for a house in a city where the average valuation is now $918,000. Hospital staff and many other public employees must be in a similar bind.
They will be hoping the capital gains tax and mortgage lending restrictions recently imposed on houses bought for rental in Auckland can arrest the rate of price rises.
But incomes have to rise, too.
Teachers in other parts of the country might resent their Auckland colleagues being paid a margin, particularly if it helps them buy a stake in the Auckland property market, but the premium may be needed to recruit and retain the teachers Auckland needs.
A bonding scheme already pays teachers more to keep them in certain schools and core subjects. Why not one to keep them in the city where housing is most expensive? Its day cannot be far away.