Iran’s Two Oil Shocks, in Today’s Dollars

OVERVIEW

What changed since 14 September

1979 was larger in real terms; 2026 is faster, and unfinished.

What changed since 14 September

Two things. WTI has climbed back above $100 (daily closes of $103.62 on 16 September and $96.41 on 22 September, against $93.39 for the first week of the month). And the comparison is now stated in August 2026 dollars, which is the only way to rank shocks fifty years apart.

The main finding

In real terms the 1979-80 shock lifted WTI 123% to $163 a barrel in today's money. The 2026 shock lifted it 66% to $102. Iran is central to both; the 2026 barrel is not yet historically expensive.

The analogy that fits, and its limit

1990 is the closest mechanical parallel: a sudden physical interruption at a chokepoint, priced in weeks. 1990 reversed in five months because the interruption ended. 2026 began to reverse and then stalled, because the interruption has not.

01 | REAL TERMS

Adjusted for inflation, 1979 was the larger shock

Real WTI rose 123% in 1979-80 and 66% in 2026.

The nominal table flattered 2026

The 14 September version compared nominal moves: 166% for 1979-80 and 70% for 2026. In real terms the gap widens slightly (123% against 66%) because inflation ran faster in 1979 and ate part of that nominal rise, while 2026 inflation has been lower.

Where the real peaks sit

The April 1980 peak equals $163 a barrel in today's dollars. The May 2026 peak was $102. The 2022 peak was $130 and the 1990 peak $90. 2026 is the smallest real peak of the five episodes and, after 1990, the fastest to reach it.

Speed, not size

1979-80 took 16 months to peak; 2026 took 4. 1979-80 needed nine months to reach the real level 2026 reached in four. The closest mechanical parallel is 1990: a sudden physical interruption rather than a slow loss of supply.

TABLE

The five episodes, nominal and real

Same baselines as before, now with August 2026 dollars.

FRED WTISPLC and CPIAUCSL. Real peak in August 2026 dollars. Months = baseline month to peak month.

02 | THE LEVEL

Today's barrel is expensive only against the 2010s

At $84 real in August, WTI sits below its 2011-14 range.

Three eras

In real terms the market has had three plateaus: the 1979-84 plateau near or above $100, the 2005-14 plateau that peaked at $206 in June 2008, and the post-2014 range mostly between $50 and $100. The 2026 spike touched the top of that range and fell back inside it by July.

What that means for the analogy

1979 changed the level of oil prices for six years. So far 2026 has produced a spike inside the existing range. Whether it becomes a level shift depends on the transit question below, not on the size of the initial move.

A caution on the early series

Before 1982 the FRED splice uses posted prices, which move in steps. The 1973 and 1979 lines are therefore smoother in the data than in the market; the peak levels are not affected.

03 | SEPTEMBER

The 1990 script called for a reversal; it stalled

WTI fell to $80 in July, then topped $100 again in September.

What 1990 did

After Iraq invaded Kuwait, WTI rose 93% in three months and gave almost all of it back within five: by February 1991 the monthly average was back near the July 1990 baseline. The supply interruption was resolved by force and the premium disappeared with it.

What 2026 has done

The 2026 path matched 1990 through the peak and the first leg down: from $102.13 in May to $80.46 in July. Then it turned. August averaged $83.90; daily closes reached $103.62 on 16 September and were $96.41 on 22 September, against $93.39 for the first six trading days of the month.

Why the difference

In 1990 the chokepoint was reopened and stayed open. In 2026 the Strait of Hormuz has been reopened, re-restricted and attacked in succession. Each renewed restriction rebuilds the premium. The 14 September version said the 1990 pattern 'may become more relevant than 1979' if transit normalized; September's prices say it has not normalized.

04 | THE MECHANISMS

Four shocks, four mechanisms

Embargo, revolution, invasion, chokepoint: the cause decides the reversal.

1973: collective producer power

The 1973-74 embargo was a coordinated act by Arab oil producers after the United States resupplied Israel during the Yom Kippur War. The State Department's record describes both an embargo against the United States and production cuts. The price doubled and then quadrupled. That episode established oil as collective leverage: producers restricting supply through a political alliance.

1979: a state crisis became a global supply shock

The second shock began with the Iranian Revolution. In January 1979 the State Department estimated Iran's lost exports at 5.0 to 5.5 million barrels a day; other producers replaced much but not all of it, leaving a net shortfall of 1.5 to 2.0 million barrels a day. The Soviet invasion of Afghanistan in December 1979 and Iraq's invasion of Iran in September 1980 widened the geopolitical frame after much of the price rise had already occurred.

2022: invasion met an already tight market

Russia's invasion pushed WTI above $110 in March 2022, but the market had already risen through the post-pandemic recovery. The war changed the distribution of Russian barrels, shipping routes and the risk premium; it does not account for the whole 2021-22 increase, which is why the baseline is January 2022.

2026: the chokepoint became the weapon

The defining feature of 2026 is direct military disruption around the Strait of Hormuz rather than a producer embargo. EIA describes military action beginning 28 February and a de facto closure of the strait; Brent began the year near $61 and ended the first quarter at $118. Announced production increases had limited value while tankers could not move normally through the Gulf.

Narrative carried from the 14 Sep 2026 version; sources unchanged.

05 | THE HOUSEHOLD BILL

What it costs a household

For the median household, the 2026 shock adds about $422 a year so far. In 1980 the oil bill took $7,088.

A simple way to measure what an oil shock costs a household is to take the nation's oil bill, all the oil Americans use priced at the cost of crude, as a share of after-tax income, and apply it to the median U.S. household income for each year, as reported by the Census Bureau. All figures here are in 2025 dollars.

In 2025 the median household had an income of $87,460, and the oil bill came to 2.2% of income, or about $1,883. With oil averaging $83.44 a barrel through August, 2026 is on course for about 2.6%, or $2,305 on the same income. The Iran shock so far adds about $422 a year.

Another way to see it is in hours of work. The median income works out to about $42 an hour over a 2,080-hour year. At that rate a barrel of oil cost 1.4 hours of pay in December 2025 and 2.0 hours in August 2026. At the pump, regular gasoline averaged $3.81 a gallon from January to September 2026, against $3.10 in 2025, or about $360 more for every 500 gallons.

Over fifty years that is about average. The median since 1973 is about $2,338. In 1980, after the Iranian Revolution and the start of the Iran-Iraq War, the median household, then earning $61,690 in today's money, gave up about $7,088, 11.5% of its income. In 2008 it was $4,695.

Measured the same way, the Arab embargo added about $1,992 a year, Iran's revolution and war $3,101, the 2008 spike $782 and Russia's invasion of Ukraine $795.

The 2026 shock costs less mainly because the economy uses much less oil for every dollar it earns. Americans use about 20 million barrels a day, close to what they used in the late 1970s, while their after-tax income is many times larger. A price spike now takes a smaller bite.

How this was measured

Oil bill: U.S. petroleum product supplied (EIA, MTTUPUS2) times the annual average WTI spot price (FRED WTISPLC, ACOILWTICO), divided by disposable personal income (BEA, FRED A067RC1A027NBEA). Household figures apply that share to Census median household income in 2025 dollars, so they assume the median household spends on oil in proportion to the national average. Median income is measured before tax, so applying an after-tax share overstates the dollars slightly. Gasoline: EIA U.S. regular all formulations retail price, including taxes (FRED GASREGM); 2026 is the January–September average. They count crude only, leaving out refining, transport and pump taxes, and include oil used by businesses, whose costs reach households through prices. 2026 is an estimate: January to August prices, 2025 oil use, and income grown at its 2025 rate.

06 | WHAT MATTERS NOW

Ask whether the barrels can move

The premium follows transit, not announced production.

For an investor

A spike inside the post-2014 range is a different asset-allocation problem from a 1979-style level shift. The evidence for a level shift is the persistence of the premium, and September is the first month that argues for it.

For a policy reader

Spare capacity on paper is not accessible supply. The 2026 market has now demonstrated that twice: in March, when the strait closed, and in September, when it was restricted again.

What would change the picture

A sustained month of normal tanker transit. If that arrives, the 1990 path resumes and the July low becomes the reference. If it does not, the comparison to make is with the 1979-84 plateau, not with 1990.

What to watch

Physical transit through Hormuz (volumes, insurance, delays); whether reopening arrangements hold long enough to remove the premium; and whether non-Gulf production reaches refiners. The September rebound came with a renewed restriction, not with new demand.

Limits

Monthly averages end in August. September is represented by five daily closes from the FRED series page and the first-week average quoted in the earlier version. Real values use CPI-U to August 2026; different baselines would change the percentages, as before.

Conditional implications, not forecasts.