The plunge in the financial markets has caused a boost for financial news.

Viewership of Fox Business and CNBC, the cable news channels devoted to corporate and economic coverage, has soared over the past week as Americans seek clarity on the current market duress.

Fox Business’s audience between April 2, when President Trump announced worldwide tariffs, and Monday was up 25 percent compared with the week before, and up 35 percent compared with its average audience last year, according to Nielsen. (Those figures reflect programming between 9:30 a.m. Eastern, when the U.S. market opens, and 5 p.m., the peak hours for business cable news.)

CNBC saw a spike during that period, too. The channel’s average viewership from 9 a.m. to 6 p.m. on Monday was up 75 percent compared with its average weekday audience since November, Nielsen said. (Fox Business is slightly ahead of CNBC in overall viewers this year, according to Nielsen.)

Investors have closely tracked the networks’ live interviews with prominent business figures, including a Wednesday appearance on Fox Business by Jamie Dimon, JPMorgan Chase’s chief executive, with the anchor Maria Bartiromo. Mr. Dimon’s interview was scheduled in advance of the April 2 announcement of Mr. Trump’s tariffs.

And viewers have watched as the networks’ anchors have scrambled on air to react in real time to dizzying market machinations. On Wednesday, Mr. Trump’s abrupt announcement on Truth Social that he had paused many global tariffs sent stocks soaring.

“Are the numbers I’m seeing on my screen correct here for the Dow?” asked the CNBC anchor Kelly Evans in the minutes after Mr. Trump’s post, as stock indexes started surging. “Wow. Our charts can’t even keep up with how quickly these numerical moves are happening.”