The researchers used a statistical method to create a "synthetic" version of Lower Hutt - essentially predicting what would have happened without the zoning reforms by comparing it to similar cities.
By 2023:
- In the real Lower Hutt (with reforms): The rental index was 1.47
- In the synthetic Lower Hutt (predicted without reforms): The rental index would have been 1.79
This means:
- Actual rents were 17.5% lower than predicted
- Or put another way, rents would have been 21.2% higher without the reforms
So it would be more accurate to say upzoning reduced rents by around 21% relatively
"Rents declined 21%" is very misleading. What were the absolute numbers results?
The researchers used a statistical method to create a "synthetic" version of Lower Hutt - essentially predicting what would have happened without the zoning reforms by comparing it to similar cities.
By 2023:
- In the real Lower Hutt (with reforms): The rental index was 1.47
- In the synthetic Lower Hutt (predicted without reforms): The rental index would have been 1.79
This means:
- Actual rents were 17.5% lower than predicted
- Or put another way, rents would have been 21.2% higher without the reforms
So it would be more accurate to say upzoning reduced rents by around 21% relatively
I updated the article with a note explaining this