“…Natural time focuses on the sequential order of the events and the analysis is usually made by using the pair ( , ), where is a quantity proportional to the size (and hence to the energy) of the th event. Natural time analysis has found useful applications in a variety of fields: Statistical Physics (e.g., [17][18][19][20][21][22][23]), Cardiology (e.g., [24][25][26][27]), Geophysics (e.g., [6,[28][29][30][31][32]), Atmospheric Sciences (e.g., [33,34]), Seismology (e.g., [35][36][37][38][39][40]), Physics of EQs (e.g., [41][42][43][44][45]), EQ prediction (e.g., [5,[46][47][48][49][50][51][52]), and so on (for a recent review see [7]). For the case of EQs [36], ∝ 10 , where is the magnitude of the th EQ and ≈ 1.5.…”