Concerns about inflation and weak consumer sentiment dragged down the stock market on Friday, as Wall Street keeps struggling to assess the path forward for the U.S. economy with the full impact of President Trump’s tariffs looming.

The S&P 500 inched down at the start of trading, after the Federal Reserve’s preferred inflation measure came in hotter than economists had expected, intensifying worries about inflationary pressures. The index later extended its decline, falling roughly 1.8 percent by midday and putting the benchmark on track for a weekly loss. Investors also digested new data from the University of Michigan that showed consumer sentiment plummeted in March.

Here’s what to know about the trading:

• Data released on Friday added to Wall Street’s angst about inflation and consumer sentiment. The Personal Consumption Expenditures price index, after stripping out volatile food and energy items, climbed 2.8 percent in February from a year earlier, faster than January’s annual pace. The data indicated that underlying price pressures intensified even before the latest escalation in President Trump’s trade war.

• Investors also assessed the latest sign that consumers are increasingly anxious about the economic outlook. Consumer sentiment plummeted 12 percent in March as expectations about inflation a year from now rose to 5 percent, the highest level since November 2022, according to data published by the University of Michigan. Earlier this week, the Conference Board reported that consumer confidence tumbled this month to its lowest level since January 2021.

• Uncertainty about the rollout of Mr. Trump’s tariffs, and their potential inflationary effects, continued to loom large, capping off a week of tariff-induced volatility. Mr. Trump announced plans on Wednesday to impose a 25 percent tariff on imported cars and some parts beginning next week. News of the impending announcement of the auto tariffs pulled down major U.S. stock indexes on Wednesday, though reaction in the broader market was relatively muted on Thursday. Analysts said investors are hoping for clarity next week, when Mr. Trump’s reciprocal tariffs, which are intended to match the tariffs imposed on U.S. goods by other countries, are set to take effect.

• The tech-heavy Nasdaq Composite fell about 2.5 percent in midday trading. Investors are closely monitoring CoreWeave’s initial public offering; the cloud computing company made its Nasdaq debut on Friday, becoming the first major artificial intelligence company to go public. Its offering had been reduced in size and value, reflecting a slumping stock market.