Left panel: frequency shifts, ⟨ Δν_{n,l = 0, 1, 2} ⟩, in μHz averaged over 15 radial orders over 1800 μHz ≤ ν< 3790 μHz as a function of the corresponding 10.7 cm radio flux, F_10.7, once the QBO signature was removed. The rising (black dots) and declining (blue dots) phases of Cycle 23, and the rising phase (red dots) of Cycle 24 are indicated by different colors. Middle panel: same as left panel, but for the low-frequency modes averaged between 1800 μHz ≤ ν< 2450 μHz. Right panel: same as the left and middle panels, but for the high-frequency modes between 3110 μHz ≤ ν< 3790 μHz.