New car and commercial vehicle registrations were down by almost a third last month as restricted trading conditions reduced sales to 8,313 new vehicles, a year-on-year decline of almost 4,000 vehicles on last May's 12,259 cars.
Overall, the Covid-19 shutdown has seen almost 20,000 fewer new cars on the road in the past five months, reflecting the effective closure of trading during the April lockdown, where only about 10 per cent of normal sales took place, according to Motor Industry Association sales numbers.
Hard hit were sales in the commercial sector, which were down 37.2 per cent to 2,912 vehicles on the back of reduced buying from the farming and building and construction industries, while the rental market reflected the stalled tourism trade.
Only 23 rental-registered vehicles drove off the lot last month, with the top seller in this category, the Toyota Hiace, moving only seven units.
Chief executive David Crawford said the lockdown made trading extremely difficult and the impact of border closures went "well beyond" sales into the car rental market.
"There are a large number of sales that go into the lease market for tourism operators, which will remain as a dead market until borders reopen or at least until we open the trans-Tasman bubble."
Crawford said it was time to accelerate out of Covid alert level 2 restrictions, as the country moves into its 11th day with no new cases and with no known community spread of the virus.
"We are better prepared for the odd case of Covid-19 should it arise, so it is time to get the economy moving forward."
Crawford said another consequence of the global pandemic response was in the car parts industry, where shortages loom.
While parts factories in China and elsewhere have reopened, air freight costs have increased "horrendously" so supply routes were being affected.
"Parts are now coming in by sea freight so that will inevitably lead to some delays, particularly in the repair and parts market."