Full data period 1968–2020 divided into the different sector structures Left panels: 1000 MC iterations where the correlation coefficients are calculated between the B_y-index and the phase randomized Z_g(NH) data series for the 2-sector structures (top panel)/4- or irregular sector structures (bottom panel). Middle panels: All 1000 individual results of the MC-iterations from the left panels aligned such that the maximum value within −13 to +13 is projected to day 0. Right panels: Averaged response of the middle panel. Note the large difference between the 2- and 4-sector structure periods.