The Wellington City Council admitted a NZ$250 million error in a cost-benefit spreadsheet, leading to postponement of consultation plans:
It's back to the drawing board for the plan to reduce speed limits to 30kph across Wellington, after one of the city council's own discovered a serious error in the council's cost-benefit analysis.
The mistake – first spotted by councillor Tony Randle – meant the benefits of reducing the speed limit in terms of reducing crashes was overstated by more than $250 million.
The mistake was "a small but significant error", Randle said. He had experience as an analyst and discovered the error after he asked council staff for the spreadsheet of cost-benefit analysis.Stuff, 19 June 2023
Follow up: The situation gets worse, as Wellington City Council release personal data in their cost-benefit analysis spreadsheet.