Figure 2. Contingency table linking volcanoes that deformed and erupted.

The table reports the number of occurrences in each category out of the 198 systematically observed volcanoes over 18 years (Table 1, Supplementary Table 1). A volcano that ‘deformed’, D, is one where at least one period of deformation has been observed with InSAR, while ‘not deformed’, , means InSAR measurements were made, but that no deformation was reported. ‘Erupted’, E, and ‘not erupted’, , volcanoes are those that erupted or not13. See Supplementary Tables 2–5 for details of individual volcanoes.