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Business reporter, BBC News
BBC Radio 5 Live
Wake Up to Money
There was further financial turbulence on Tuesday when stock markets around the world climbed sharply higher, as investors grappled with the economic impact of Covid-19.
The S&P 500 and London's FTSE 100 enjoyed their best days since the 2008 financial crisis, rising more than 9%.
Tom Stevenson, investment director at Fidelity International, said it was down to "governments and central banks around the world now acting together massively to inject stimulus into the economy. Governments are spending money, and central banks are giving the liquidity the system needs."
"That's been the big worry for markets recently, around how much was being done. So, when it became clear that a $2tn support package was apparently in the offing in the US, that sparked a rise in the markets."
He added: "It's good news, but we're not out of the woods yet. When markets are falling, you get these big rallies, but you shouldn't get stuck on that. They do bounce around in these situations."
Some more massive drops again today for shares.
The biggest faller in the FTSE 100 was cruise company Carnival.
It lost more than a third of its value - 34.22% - to fall to 620p. In mid January it stood at 3,114p.
Aerospace giant Meggit fell a quarter to 238,40p, while the Ashtead Group fell 23.30% to 1,300p.
The blue-chip index closed down 4.05%, after losing 214.32 points, at 5,080.58.
The wider FTSE 250 lost 6.58%, or 916.69 points, to fall to 13,008.19
There was a moment there - as you can see from our graph above - when the FTSE 100 like it might recover some of today's losses.
But it's slipped downwards again and is now down 4.21%.
However, it does look likely to remain above the 5,000 level today. Possibly!