Industrial action by members of the Public Service Association is leading to a delay in the release of important information.
Statistics New Zealand said it would have to delay the release of the Food Price Index for November.
The index showed the rate of change in the price of food and food services purchased by households.
Deputy chief executive of Statistics Kelvin Watson said he respected the staff's rights to take industrial action, and the department was working to minimise the effects of the delay.
An average wage increase of three percent had been offered to staff.