Odds On: Polymarket gives 48% chance Hormuz normalizes by April 30

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BACKGROUND: On February 28, the United States and Israel launched joint military strikes against Iran, after which shipping traffic in the Strait of Hormuz fell sharply amid attacks and threats against commercial vessels. The strategic waterway was effectively brought close to a standstill within days, with many tankers and cargo ships anchoring outside the strait while operators assessed the risks.

According to IMF PortWatch data, the strait historically averaged around 95-105 commercial vessel transits per day in January and February, handling roughly 20% of global seaborne oil flows, before dropping to roughly 6-7 ships per day in early March, a level that persisted on average through April 12, representing a near-shutdown of one of the world's most critical energy chokepoints.

Brent crude and WTI both climbed sharply in the wake of the disruption, reflecting concern about supply risk through Hormuz, though moves stayed below the most extreme levels seen in past oil shocks. The U.S. Energy Information Administration and other forecasters flagged Hormuz-related risks in their outlooks, while stressing that global demand conditions and alternate supply routes will shape how persistent any price impact proves to be.

This morning, Iranian officials signaled that the strait is open for commercial traffic under the current ceasefire, provided ships avoid designated exclusion zones and comply with new security protocols. U.S. officials have welcomed tentative de-escalation but warned that naval forces will continue to monitor and escort traffic in the waterway until attack risks recede. Oil prices pulled back on the headlines, with Brent and WTI giving back part of their recent risk-premium gains, while equity markets staged a relief rally on hopes that the worst-case supply scenarios can be avoided for now. Commercial operators and insurers cautioned that actual tanker resumption still depends on conditions on the water, with some vessels electing to wait for several incident-free days before re-entering the strait.

THE BET: Polymarket lists the contract "Strait of Hormuz traffic returns to normal by end of April?" which uses IMF PortWatch data to determine whether shipping activity reaches a predefined threshold. The market currently shows an implied probability of 48% for the "Yes" outcome and cumulative trading volume of approximately $13M. On April 7, separate reporting noted that the probability had risen to approximately 57% at that time, with trading volume then around $4.07M.

THE RULES: This market resolves "Yes" if IMF PortWatch publishes a 7-day moving average of transit calls for the Strait of Hormuz equal to or above 60 for any date between market creation and April 30. Otherwise, it resolves "No." Daily transit calls include container, dry bulk, roll-on/roll-off, general cargo, and tanker ships. Ships not reported by IMF PortWatch will not be considered.

Resolution occurs as soon as the threshold is met, or once data has been published for April 30 without meeting it, subject to a 14-day window for that date's data to appear. Revisions to previously published data points within the market's timeframe will be considered and will not disqualify a qualifying value. Revisions made after April 30 data is published, however, will not be considered.