Figure S4. Histograms of hourly maximum C(T). (a) C(T) calculated for 14 non-earthquake periods (2:15-10:00 UT on DOY30, DOY31, DOY40, DOY49, DOY50, DOY60, DOY63, DOY72 and DOY73 in 2011, DOY96 and DOY116 in 2016, 12:15-20:00 UT on DOY96 and DOY116 in 2016). Colors corresponds to Kp indexes. (b) Normalized histogram of Figure S4a. Lines connecting bars show boundary between Kp=1+ and 2-, and Kp=4 and 5-.