Trader consensus favoring zero VEI ≥4 eruptions in 2026 (57.5% implied probability) stems primarily from the absence of any confirmed events meeting that threshold through mid-August, despite dozens of lower-intensity eruptions worldwide. VEI 4 events require substantial tephra volumes (≥0.1 km³) and plume heights often exceeding 10 km, criteria that ongoing activity at sites like Indonesia’s Dukono (VEI 3) and Russia’s Sheveluch (high ash plumes but sub-VEI 4 episodes) has not yet satisfied. Historical baselines show such eruptions occur irregularly—typically one to a few per year on average—yet 2026 monitoring data from the Smithsonian Global Volcanism Program and national observatories indicate predominantly effusive or moderate explosive behavior so far. This scarcity, combined with typical year-to-year variability and no major escalation signals in recent USGS or PVMBG reports, underpins the market’s strong lean toward zero or one outcome while leaving room for late-year surprises at restless systems.