President Trump slammed oil companies in an early-morning social media post on Wednesday for prices at the pump that are not falling as quickly as crude oil prices since energy began flowing more freely through the Strait of Hormuz.
“Customers are being ‘gouged,'” the president wrote on Truth Social just after midnight, adding that he had instructed his Department of Justice to investigate. “Gasoline prices better start going down a lot faster than what I’m seeing!”
Trump’s frustration with the lag is a common one among presidents — it flummoxed President Biden just a few years ago — and is reflected in price fluctuations in recent weeks.
Both crude oil and pump prices have been falling over the last week, but crude has moved down at a faster pace. International benchmark Brent Crude is down over 5% between June 18th and 24th, according to Yahoo Finance data.
Read more: When will gas prices go down?
But the national average of gasoline in the US tracked by the American Automobile Association (AAA) shows a more modest 2.5% drop over the same period from about $4.02 to $3.92 per gallon.
Over the last month, crude oil prices have been down over 27% while gas prices have been down 13%.
It’s clearly a frustration for Trump and comes in the face of repeated promises from the president and his aides that, once the Strait of Hormuz opens, the pain being felt by drivers would ease as prices drop “like a rock.”
At times, the president and his team have also promised that Americans would quickly see pump prices lower than the average of $2.98 per gallon before the war in Iran began.
Yet energy observers have often described the tendency of prices to ease after an oil shock as fluttering down more slowly.
As the Federal Reserve Bank of St. Louis explained in 2022, crude oil and refined gas prices don’t always move in tandem, a phenomenon known as “rockets and feathers.” They often shoot upward together (like a rocket), but when crude oil prices later fall, gasoline prices sometimes drift down at a much slower rate (like a feather).
The formal economic term for the phenomenon is “asymmetric pass-through,” and it stems from a variety of causes in energy markets, primarily the lag between refiners buying crude oil and then selling their refined product. Profit-taking is another factor as firms preemptively protect their bottom lines in moments of uncertainty by raising prices more quickly.
What it means in practice is that drivers are often the last to feel relief when oil shocks ease, and that can lead to outsized political costs from angry voters.
In the aftermath of Russian President Vladimir Putin’s invasion of Ukraine in 2022, both crude oil and pump prices spiked. Prices at the pump stayed elevated for months, even after crude oil prices came down, frustrating Biden and his aides to no end.
In a March 16 briefing of that year, then-Press Secretary Jen Psaki said, “many accept that gas prices rise quickly but fall slowly — the so-called ‘rockets-and-feathers’ phenomenon — but President Biden rejects that.”
Biden’s approach was to have the Federal Trade Commission (FTC) investigate the price increase, making similar charges to Trump that customers were being gouged.
But the pressure campaign had little effect and — in what could be an ominous sign for Trump — Biden was still focused on the issue four months later.
He posted that July, appealing to stations to “bring down the price you are charging at the pump. And do it now.”
Ben Werschkul is a Washington correspondent for Yahoo Finance.
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