"These elements alone would have strongly mitigated the stop-start impact to the economy."
Vaccine tracking data by the Financial Times showed that only 7.8 per cent of the total New Zealand population had received a full vaccination by June 22.
Australia has fared even worse, with only 4.7 per cent of its population fully vaccinated.
By comparison, Israel has vaccinated 57 per cent of its population, the UK 48 per cent and Chile 52.3 per cent.
New Zealand's current vaccination rate places the country behind Peru, Ecuador, Malaysia and India.
Barnett questioned whether New Zealand had been somewhat complacent given we haven't had the constant threat of community cases.
Countries that have been heavily affected by continuous lockdowns have tended to place greater emphasis on getting the population vaccinated as quickly as possible.
Barnett added it was necessary for New Zealand to adopt a vaccine travel pass to keep better track of who has been vaccinated.
He has recommended the ICC AOKpass that is currently being promoted by the International Chamber of Commerce.
The pass is a risk-mitigation tool that allows users to present digitally authenticated and secure medical records to border authorities and government administrations.
It helps to provide a consensus between participating countries or businesses on what constitutes an acceptable vaccine and when people are allowed to travel.
Travel passes are already being used in Europe for big events, most notably the Euro 2021 football championships.
Fans travelling to the major destinations are required to provide proof of full vaccination against coronavirus or a negative lateral flow Covid-19 test within 48 hours before being admitted into the stadium.
A total of 13 countries in Europe are already using the vaccine passport, including Germany, Greece and Spain.
There has, however, been some controversy in Europe in that travellers who have been vaccinated with Russian, Chinese and Indian vaccines may not be allowed to enter the EU in the coming months.
Only four vaccines have so far been approved by the European Medicines Agency.
These include Pfizer, Moderna, AstraZeneca and Johnson & Johnson.
A number of other vaccines are going through the approval process.
The New Zealand Government favours the Pfizer vaccine, but a group of New Zealanders will be the first humans to trial a new second-generation Covid vaccine out of China.
As the vaccine rollout continues, it will be necessary for countries to ensure a consensus on what constitutes an acceptable vaccine to allow for safe travel.