NEW YORK — U.S. stocks climbed Wednesday after the Federal Reserve said the economy still looks healthy enough to keep interest rates where they are. Wall Street also got a boost from easing yields in the bond market.

The S&P 500 jumped 1.1%, and its gains accelerated following the Fed’s announcement. The Dow Jones Industrial Average added 383 points, or 0.9%, and the Nasdaq composite rose 1.4%.

The rally followed weeks of sharp and scary swings for the U.S. stock market. Uncertainty is high about how much pain President Donald Trump will allow the economy to endure in order to remake the system as he wants. He’s said he wants manufacturing jobs back in the United States and far fewer people working for the federal government.

Trump’s barrage of announcements on tariffs and other policies have created so much uncertainty that economists worry U.S. businesses and households may freeze and pull back on their spending.

Fed Chair Jerome Powell acknowledged the rising pessimism among U.S. consumers and companies shown by recent surveys, but he also pointed to data showing the economy is solid at the moment, such as a relatively low unemployment rate. He said it’s possible to have periods where “people say downbeat things about the economy and then go out and buy a new car.”

“Given where we are, we think our policy is in a good place to react to what comes, and we think that the right thing to do is to wait here for greater clarity about what the economy’s doing,” Powell said.

The Fed has been holding interest rates steady this year, after cutting them sharply through the end of last year. While lower rates can help give the economy a boost, they can also push inflation upward.

Fed officials indicated they’re still penciling in two cuts to the federal funds rate by the end of this year, just as they were forecasting at the end of last year. But they are also seeing weaker growth for the U.S. economy and higher inflation than they were before.

“What would you write down?” Powell said when asked about the continued forecasts for two cuts. “It’s really hard to know how this is going to work out.”

That raises fears about what’s called ” stagflation,” where the economy stagnates but inflation remains high. The Fed doesn’t have good tools to fix such a toxic combination. Powell said he doesn’t see a return of stagflation, which the U.S. economy suffered in the 1970s. “I wouldn’t say we’re in a situation that’s remotely comparable to that,” he said.

Stocks also got a boost from lower Treasury yields in the bond market.

The yield on the 10-year Treasury dropped to 4.24% from 4.31% just before the Fed announced its decision. When bonds are paying investors less in interest, they can encourage investors to pay higher prices for stocks, which can offer higher returns in the long term.

Besides holding its main short-term interest rate steady, the Fed also said it will begin paring the monthly reductions of its trove of Treasurys beginning in April. That means it will allow only up to $5 billion of its massive trove of Treasurys to mature each month, down from a prior cap of $25 billion. By reinvesting more in Treasurys each month, the Fed will essentially be helping to keep longer-term yields lower than they would otherwise be.

Powell repeated several times that the move was more technical than a signal about coming changes in policy. He said it was the result of seeing “some signs of increased tightness in money markets.”

“It isn’t sending a signal in any hidden way,” he said.

On Wall Street, Nvidia helped support the market after rising 1.8% to cut its loss for the year so far to 12.5%. It hosted an event Tuesday where it largely “did a nice job laying out the roadmap” and fighting back against speculation the artificial-intelligence industry is seeing a slowdown in demand for computing power, according to UBS analysts led by Timothy Arcuri.