The S&P 500 surged 5.6% at the open after plunging 9.5% Thursday in the biggest rout since 1987 and fifth worst on record. European equities jumped 7%, the dollar surged and stress in the credit markets showed some signs of easing.

After days of no or inadequate action, policy prescriptions came fast Friday, with reports Congress is near a deal on a spending bill. The European Union prepared to suspend government spending rules and regulators in Italy and Spain banned short-selling on some stocks. China’s central bank said it would pump in $79 billion to bolster the economy.

The moves buoyed market sentiment battered by the spread of the virus and a spate of travel restrictions, school closings and event cancellations. But bears cautioned that the rebound was preordained and may not stick.

After each of the 10 worst days in S&P 500 history, the average return has been a gain of 2.94%. The Cboe Volatility Index dropped after its fourth-highest close on record. Such spikes in the VIX have always been followed by sharp rallies.

Other markets remained exceptionally volatile. Ten-year Treasuries swung from earlier gains to losses. Sovereign bonds sank across most of Europe for a second day amid criticism of European Central Bank measures to address the pandemic. Oil pushed higher and the dollar headed for its best week since 2016.

“It’s possible we’re just recovering a portion of yesterday’s losses on the idea that there were no terrible headlines this morning,” said Susquehanna Financial Group strategist Christopher Jacobsen. “The market had priced in the extreme dour outcome and the lack of newsflow this morning to confirm that worst-case scenario resulted in just a bit of a relief rally.”

Even with Friday’s gains, global equities are heading for their worst week since 2008 as investors price in a severely weaker economic outlook. They’re doubting the efficacy of policy responses as cases continue to grow across the world and restrictions on people and businesses crush sentiment. The Bank of Japan on Friday followed an earlier move from the Federal Reserve to inject liquidity.

“It seems that the more severe things become in the short term, the more extreme will be the fiscal and monetary policy response,” Mark Dowding, chief investment officer at BlueBay Asset Management, wrote to investors. “It is very conceivable that the full boost from such measures will only really kick in just as activity rebounds, with pent up demand leading to a turbo-charged recovery in the second half of the year in the wake of an economic contraction in the context of the first half.”

These are the main moves in markets:

Stocks

• The S&P 500 Index jumped 6% as of 9:31 a.m. in New York.
• The Stoxx Europe 600 Index soared 6.6%.
• The MSCI Asia Pacific Index dipped 2.2%.
• The MSCI All-Country World Index climbed 1.2%.

Currencies

• The Bloomberg Dollar Spot Index increased 0.4%.
• The euro decreased 0.3% to $1.1149.
• The British pound declined 0.7% to $1.2484.
• The Japanese yen weakened 2.5% to 107.28 per dollar.
• The Mexican peso strengthened 2.5% to 21.403 per dollar.

Bonds

• The yield on 10-year Treasuries gained 13 basis points to 0.93%.
• The yield on two-year Treasuries climbed two basis points to 0.50%.
• Germany’s 10-year yield jumped 16 basis points to -0.58%.
• Japan’s 10-year yield increased 11 basis points to 0.054%.

Commodities

• West Texas Intermediate crude rose 6.6% to $33.57 a barrel.
• Iron ore was unchanged at $88.20 per metric ton.
• Gold strengthened 0.6% to $1,586.14 an ounce.
• LME zinc climbed 3.4% to $2,004 per metric ton.

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