Cumulative probability distributions (c.d.f.s) of the power input to the magnetosphere, P_α, as a ratio of its mean value P_o = <P_α>_all for the full interval of near-continuous interplanetary data (1995–2017, inclusive). The P_α/P_o data are divided into 288 bins: 36 equal-sized bins in fraction of year F and the same eight 3-h Universal Time (UT) bins over which the range am index is evaluated. For each F–UT bin the c.d.f. of P_α/P_o as a ratio of the mean value for that bin <P_α/P_o>_F,UT was plotted and colored according to the value of that ratio. The black line is for all P_α/P_o data, the orange line for the F–UT bin giving the largest <P_α/P_o>_F,UT and the green line for the F–UT bin giving the smallest <P_α/P_o>_F,UT.