Heliophysics Events Knowledgebase[^5] (HEK). Flare locations are determined by subtracting the SDO/*Atmospheric Imaging Assembly* (AIA: @leme12) 131Å image closest to the GOES start time, from that image closest to the GOES peak time. The flare location is then extracted from the peak intensity of this difference image (S. Freeland; private communication, 2017). Knowing the timing and position of each event then allowed this information to be cross-referenced with the metadata from other instruments to determine whether or not they observed the same location at the same time. *Note that this does not guarantee that a given instrument actually detected flaring emission, but only that the timing and pointing of a given dataset were consistent with the timing and location of the flare.* B-class flares were not included in this study due to discrepancies between flare locations derived from RHESSI and SDO/AIA and were therefore deemed unreliable. The SSW Latest Events list also has several months of data missing[^6]. Nevertheless, out of the 8090 flares of GOES class C1 or greater that appear in the NOAA event list, 6953 (86%) are also in the SSW Latest Events list and include location information.

![Solar Cycles 23 and 24 (average monthly sunspot number) 