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The Federal Reserve has committed to keeping interest rates lower for longer. But will that be enough to support an economy grappling with a historic shock, especially with Congress at an impasse on additional government spending?

That’s the big question from investors ahead of the Fed’s Wednesday meeting, its last before the November election.

Having already slashed interest rates to near zero and added roughly $3 trillion to the central bank’s balance sheet, Chair Jerome Powell is expected to lean more heavily on forward guidance, telling businesses and investors more clearly what they can expect in the quarters and years ahead.

Any reassurances, however, may have a limited impact given already dovish expectations. Markets appear to have written off an interest rate hike by the Fed before 2025, according to UBS.

Big picture: The huge shock to many of the world’s biggest economies from the coronavirus pandemic may not be quite as bad as economists feared just a few months ago.

In a report published on Wednesday, the Organization for Economic Cooperation and Development upgraded its forecast for global economic output this year, noting that while declines were still “unprecedented in recent history,” the outlook has improved slightly since June.

The Paris-based agency said it now expects the world economy to shrink by 4.5% in 2020 before expanding by 5% in 2021. Previously, the OECD said it thought the global economy would contract by 6% this year and grow 5.2% next year.

The OECD predicts that the US economy will shrink 3.8% this year, compared to the massive 7.3% hit forecast in June.

But the outlook depends in large part on continued support from policymakers. The forecast assumes that central banks like the Fed will keep easing without worrying too much about a spike in inflation, and that US lawmakers will approve another stimulus package worth up to $1.5 trillion this fall, even though negotiations have reached an impasse.

Watch this space: The Fed is also due to release its latest economic projects on Wednesday. It’s expected to include a significant upgrade to prospects for near-term growth, per Deutsche Bank’s Jim Reid.

This is the biggest software IPO ever

A Silicon Valley darling backed by Warren Buffett just pulled off the biggest software IPO in history, according to Renaissance Capital.

What’s happening: Shares of Snowflake, a provider of cloud-based databases, will start trading on the New York Stock Exchange Wednesday under the ticker “SNOW.”

The company raised $3.36 billion through the offering after pricing its stock at $120 per share, ahead of expectations.

Why it matters: The public offering, which is generating plenty of buzz, is a sign of just how hot demand for cloud computing is in the work-from-home era.

Even billionaire Buffett is interested, with Berkshire Hathaway committing to a $250 million investment via a private placement after the market debut. Salesforce also plans to buy $250 million worth of stock.

But like many hyped-up tech startups, Snowflake isn’t making money. Though revenue grew 174% for its fiscal year ending in January, the company still booked a $349 million net loss.

Coming up: According to Renaissance Capital, this September is poised to be the busiest by deal count since 1999. The secretive data-analytics company Palantir and workplace app Asana are among the big names due to make their trading debuts later this month.

Nikola is under serious pressure

For a while, Nikola was flying high, with shares in the electric truck startup skyrocketing as investors lent their support to the Tesla competitor.

Now, the company is coming under pressure. A report from a short seller betting against popular firms — which alleged a range of misdeeds, including that Nikola and its founder Trevor Milton presented a prototype truck as being closer to market than it actually was — has rocked shares in recent days.

And while Nikola’s stock rose after the company issued a rebuttal to the short seller on Monday, shares are down again in premarket trading after the Financial Times reported that the US Department of Justice has started looking into claims about the firm.

Step back: Nikola, which made its public debut earlier this year via a merger with a “blank check” acquisition company, has been a big beneficiary of the boom in trading from casual investors using platforms like Robinhood. But the dramatic stock movements in the past week are a reminder that it’s far from a sure bet, even after the company inked a $2 billion deal with General Motors.

Up next

US retail sales for August post at 8:30 a.m. ET. The Federal Reserve announces its latest policy decision at 2 p.m. ET.

Coming tomorrow: The Bank of England and Bank of Japan hold meetings, though little action is expected this round.