Solar cycle evolution of coronal rotation. The top two panels show the azimuthally averaged rotation rate at the source surface of the PFSS models using WSO magnetograms (1976–2022) and SOHO/MDI & SDO/HMI magnetograms (1996–present), respectively. The third panel displays the average brightness of scattered white light from streamers at three solar radii observed by SOHO/LASCO-C2. The bottom row displays the monthly sunspot number during this time, taken from WDC-SILSO, along with the contributions from the northern and southern hemispheres individually.