Panel a: time variation of averaged monthly (total) sunspot area during solar cycles 14–24 after performing 13-month running average. Panel b: same in the northern (blue curve) and southern (red curve) hemispheres, respectively, during that period. Panel c: hemisphere-wise excess activity: the blue-filled colour indicates the total area associated with the north hemispheric sunspots to be higher than the southern hemispheric total sunspot area and the red-filled colour depicts the opposite scenario. Panel d: variation of unsigned polar flux with error bars in two hemispheres. The rectangular grey bars depict episodes of solar minimum during 1906–2016.5.