Extended Data Fig. 8. Degree of waveform change plotted on time interval between repeating events and average time distance from the predicted times of reversal.

Specifically, the distance is measured as the absolute value of the date of the first repeat minus the starting date predicted for the observed recurrence time, plus the absolute value of the date of the later repeat minus its predicted date. At intervals greater than 10 years between repeaters, most similar-waveform event pairs are much less than a year away from the pair of dashed-line predictions in Fig. 4.