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The rotational profile of the Sun is considered to be one of the key inputsin a solar dynamo model. Hence, precise and long-term measurements of thisquantity is important for our understanding of solar magnetism and itsvariability. In this study, we use the newly digitized, white light sunspotdata (1923 -- 2011) from Kodaikanal Solar Observatory (KoSO) to derive thesolar rotation profile. An automated correlation based sunspot trackingalgorithm is implemented to measure the rotation parameters, $A$, theequatorial rotation rate and $B$, the latitudinal gradient. Our measurements of$A=14.381\pm0.004$ and $B=-2.72\pm0.04$ compare well with previous studies. Inour analysis, we find that the bigger sunspots (with area $>$400~$\mu$Hem)rotate slower than the smaller ones. At the same time, we do not find anyvariation in the rotation rates between activity extremes, i.e solar maxima andminima. Lastly, we employ our tracking algorithm on the Michelson DopplerImager (MDI) data and compare the MDI results with our KoSO values.

Measurements of Solar Differential Rotation Using the Century Long Kodaikanal Sunspot Data