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For the years 2001-2008, we use full-disk, SOHO/EIT 195 $\AA$ calibratedimages to determine latitudinal and day to day variations of the rotation ratesof coronal holes. We estimate the weighted average of heliographic coordinatessuch as latitude and longitude from the central meridian on the observed solardisk. For different latitude zones between $40^{o}$ north - $40^{o}$ south, wecompute rotation rates, and find that, irrespective of their area, number ofdays observed on the solar disk and latitudes, coronal holes rotate rigidly.Combined for all the latitude zones, we also find that coronal holes rotaterigidly during their evolution history. In addition, for all latitude zones,coronal holes follow a rigid body rotation law during their first appearance.Interestingly, average first rotation rate ($\sim 438 nHz$) of the coronalholes, computed from their first appearance on the solar disk, match withrotation rate of the solar interior only below the tachocline.

Rotation rates of the coronal holes and their probable anchoring depths