The dial has required regular maintenance throughout existence. The markings were replaced many times over the centuries and, despite restorations overseen by a professor of natural sciences and a historian of science, Robert Gunther, more and more errors crept into the pillar's tables. The dial also developed a lean. This was fixed in 1967 after it was discovered that the dial had no solid foundation and that its base was made of stone panels loosely packed with rubble. In 1976, the sundial was restored (and its tables corrected) to its state 1710 by Philip Pattenden. Since the 1710 tables were designed for the Julian calendar, they have no modern use. The sundial was most recently restored in 2016.