Table 4. Cross-correlation coefficients between the sunspot number (SSN) and solar, interplanetary, and geomagnetic (SIG) parameters

	SMMF	SFI	10.7 cm radio flux	IMF
Lag (months)	+6	0	0	+4
Cross-correlation	0.7789	0.8501	0.9783	0.7137
	TSI	Pdyn	Ap index	GCR intensity
Lag (months)	+1	+12	+11	+8
Cross-correlation	0.8445	0.3713	0.4822	−0.8282

SMMF, solar mean magnetic field; SFI, solar flare index; IMF, interplanetary magnetic field; TSI, total solar irradiance; GCR, galactic cosmic ray.