Social costs measure the total cost of road crashes to the nation, including loss of life and life quality, loss of productivity, medical, legal, court and vehicle damage costs. Injury costs are classified into fatal, serious, and minor injuries as reported by crash investigators. Te Manatū Waka updates the social cost of road crashes and injuries annually to allow comparison of the costs and benefits of any road safety actions in current dollars.
These updates provide estimates of average social costs that account for:
- any inflationary effects that affect different cost components
- any changes in the number of crashes by region, area, and severity
- any changes in the average number of injuries involved in a crash by region, area, and severity.
This report outlines the methodology used to estimate the average social costs and provides some guidance on using the estimates. It should be read in conjunction with the estimates provided for the 2022 update onwards.
Social cost of road crashes and injuries - Methodology and user guide
The work to date
The 2023 update
This is an annual update of the social cost of road crashes and injuries published by Ministry of Transport Te Manatū Waka. This update provides estimates of the average social costs per injury and per crash at June 2023 prices and is based on crash and injury data from 2020 to 2022.
The 2022 update
This is an annual update of the social cost of road crashes and injuries published by Te Manatū Waka. This update provides estimates of the average social costs per injury and per crash at June 2022 prices and is based on crash and injury data from 2019 to 2020. This update also incorporates the new Value of Statistical Life that was based on this study.
The 2021 update
This is an annual update of the Social Cost of Road Crashes and Injuries published by the Ministry of Transport. This update provides estimates of the average social cost per injury and per crash at June 2021 prices. The update accounts for any changes in the numbers of crashes by area and severity and is based on crash and injury data from 2018 to 2020, supplemented by hospital admissions data and Accident Compensation Corporation’s injury claims data.
To ensure we target our road safety resources most effectively, the cost of any safety interventions should be evaluated against the resulting benefit expressed in terms of social cost. When there are a number of potential solutions to a transport problem, using social cost information allows us to make consistent comparisons between solutions, especially when these solutions have different impacts on the risks of crashes and the injuries that may be sustained in them. Updated social cost estimates are incorporated into Waka Kotahi NZ Transport Agency’s Crash Analysis System (CAS) to facilitate this.
The 2020 update
This is an annual update of the social cost of road crashes and injuries published by Te Manatū Waka. This update provides estimates of the average social costs per injury and per crash at June 2020 prices and is based on crash and injury data from 2017 to 2019.
The 2019 update
This is an annual update of the social cost of road crashes and injuries published by Te Manatū Waka. This update provides estimates of the average social costs per injury and per crash at June 2019 prices and is based on crash and injury data from 2016 to 2018.
The 2018 update
This is an annual update of the social cost of road crashes and injuries published by Te Manatū Waka. This update provides estimates of the average social costs per injury and per crash at June 2018 prices and is based on crash and injury data from 2015 to 2017.
The 2017 update
This is an annual update of the social cost of road crashes and injuries published by Te Manatū Waka. This update provides estimates of the average social costs per injury and per crash at June 2017 prices and is based on crash and injury data from 2014 to 2016.
Get in touch
info@transport.govt.nz