"Providing generic economic forecasts in the current environment is a complete waste of time," said BNZ's Toplis.
"Whatever numbers we might concoct are nothing more than poorly educated guesswork. Without knowing how the spread of Covid-19 is going to evolve, specifics become meaningless.
"While we can't identify magnitude, we can identify direction and what to look out for."
The bottom line is that GDP in the first quarter will be flat and faces a massive fall in the second quarter.
"Beyond that, it is highly dependent on how the virus evolves," he said.
"We do not expect the level of activity in the economy to return to where it was at the end of 2019 until 2022 at the earliest."
The scale of the shock makes it easy to get sidetracked on the implications for geo-political change, social change - the idea that the world is entering a new era.
But for now, and for our sanity, let's keep the focus more tightly on the latest assessments by the world's economic heavyweights.
In her latest statement, International Monetary Fund (IMF) managing director Kristalina Georgieva described the outlook as "a recession at least as bad as during the global financial crisis or worse."
She warned that emerging markets face the biggest hit.
"Investors have already removed US$83 billion from emerging markets since the beginning of the crisis, the largest capital outflow ever recorded," she said.
"Advanced economies are generally in a better position to respond to the crisis, but many emerging markets and low-income countries face significant challenges. They are badly affected by outward capital flows, and domestic activity will be severely impacted as countries respond to the epidemic."
There was a small note of optimism.
"We expect recovery in 2021," she said.
But that recovery is likely to be long and challenging.
"What you have is an economic effect now that, very clearly, is going to be prolonged beyond the period of the pandemic," Gurria told CNBC.
"We'll hopefully get rid of the pandemic in the next two or three months and then the question is how many unemployed [will there be], how many small and medium-sized enterprises will be in a very, very severe situation if not disappeared by that time."
Overnight, the US Federal Reserve made another huge move to support credit markets and keep borrowing costs low.
Announcing an unlimited programme of bond-buying it moved its focus from financial markets to the wider economy.
For the first time ever it will purchase corporate bonds and make direct loans to companies.
It will also roll out a credit programme for small and medium-sized business.
With no cap on its bond-buying potential, we are now in a world of "infinite quantitative easing".
Somewhat predictably for the human race, pressure on the global economy is being made worse by politics.
Two big issues are amplifying the immediate financial risk:
• US political gridlock: A US$2 trillion fiscal stimulus plan that would buoy markets and reassure US business is stalled in the Senate as Democrats and Republicans fight over its details.
• The oil price war between Russia and Saudi Arabia: The bizarre stand-off between the two oil-producing nations has crashed prices putting energy-producing nations at risk. An agreement to cut supply would restore some balance to energy markets and take pressure off credit markets.
These issues are a reminder that despite much of this crisis being beyond our control, how we get through will depend greatly on how we all behave.