This work is supported by the National Natural Science Foundation of China grants 41774194, 41504125, 41531072, and 41674166 and the Construct Program of the Key Discipline in Hunan Province. We thank J. H. King, N. Papatashvilli, and CDAWeb for the use of magnetospheric indices and acknowledge the University of Iowa as the source for the EMFISIS data (this acknowledgment does not imply endorsement of the publication by the University of Iowa or its researchers). We acknowledge H. Spence, G. Reeves, D. Baker, S. Kanekal, and A. Jaynes for the use of ECT data. Data are available at the following websites: http://cdaweb.gsfc.nasa.gov/cdaweb/ istp_public/ (geomagnetic activity indices), http://emfisis.physics.uiowa.edu/Flight/ (EMFISIS), and http://www.RBSP-ect. lanl.gov/ (ECT).