Reuben Rose-Redwood and Li Li compared Randel's elevation data to modern data and found that while there had been some levelingin general the West Side had been smoothed out and the East Side had been filled inthe overall average change was low. Rose-Redwood commented: "he majority of the alterations were only on the order of a few meters or less, and the historical profiles of Manhattan's avenues are very similar to the contemporary transects of those same thoroughfares." Infilling led to an average increase of and excavation to an average decrease of , but the West Side remains hillier than the East Side, just as was the case before the grid. Rose-Redwood writes that "Manhattan remains an 'island of hills' ..."