Fig. 3: The least-square fitted ~8.5 yr signals from different records.
From: Inner core static tilt inferred from intradecadal oscillation in the Earth’s rotation

From (a) the first-order time derivative of length-of-day variations (dΔLOD/dt); (b) the x component of the polar motion (PM), and (c) the y component of the PM. The time span used is 1900–2020, and the sampling interval is one year.