There are concerns scrapping the traditional census won't deliver the desired results. 

Stats NZ is moving to a system using Government collected admin-data, saying the current five yearly Census is financially unsustainable. 

Census-style questions will still be asked in much smaller annual surveys looking at a small fraction of the population. 

Former national statistician Len Cook told Mike Hosking data-wise, this won't cut it. 

He says admin-data comes from about a dozen different sources, none of them complete. 

LISTEN ABOVE