Global seismic monitoring by the USGS shows that the planet typically records 10 to 15 earthquakes of magnitude 5.5 or greater each week, driven by ongoing tectonic activity along major fault zones such as the Pacific Ring of Fire. This baseline positions the greater-than-nine outcome as the leading market-implied probability at 35 percent, with traders incorporating recent moderate activity including several M5.5-plus events in Chile, Tonga, and Indonesia during mid-May. No significant clustering or foreshock sequences have emerged in the past 48 hours to push counts substantially higher or lower, preserving the spread across the 6-to-9 range. Continuous real-time updates from the USGS catalog will determine final resolution as the May 18–24 window opens.