The numbers: The consumer-price index dipped 0.4% last month, the biggest decline in five years, the Labor Department said Friday. The drop was in line with the forecast of economists surveyed by MarketWatch.

Core inflation, minus food and energy, prices fell 0.1% in March, the first decline in 10 years. The rate of inflation over the past 12 months fell to 1.5% from 2.3%. Core inflation slowed to 2.1% in March from 2.4% in February.

In the year to March, overall prices rose 1.5%, while core prices were up 2.1% on the year, the Labor Department said.

What happened: The energy index fell 5.8% in March after seasonal adjustment while the cost of gasoline fell 10.5%. Food prices rose 0.3%, pushed higher by a 0.5% gain in the cost of food at home. The core rate of inflation was driven lower by declines in airline fares, lodging away from home, and apparel. Medical care costs rose in the month.

Big picture: The COVID-19 pandemic’s shutdown of businesses is creating massive slack in the economy, and price pressures are expected to continue to fall in coming months. Once the economy opens up, there is more of a debate. Some economists think core inflation will continue to drift down. Federal Reserve Chairman Jerome Powell backed this view on Thursday, saying he wasn’t worried about a spike in inflation.

What are they saying? “The March consumer price report underscores that the fallout from the coronavirus has had a large disinflationary effect on prices due to the large demand shock, plunge in oil prices, and stronger dollar. The disinflationary impulse, along with the great disruption in economic and financial market activity, is a key reason why the Fed is unleashing vast new monetary policy stimulus,” said Gregory Daco, chief U.S. economist at Oxford Economics.