A 2007 study compared fifteen major urban dialects on the objective criteria of lexical similarity and regularity of sound correspondences, and subjective criteria of intelligibility and similarity. Most of these criteria show a top-level split with Northern, New Xiang, and Gan in one group and Min (samples at Fuzhou, Xiamen, Chaozhou), Hakka, and Yue in the other group. The exception was phonological regularity, where the one Gan dialect (Nanchang Gan) was in the Southern group and very close to Meixian Hakka, and the deepest phonological difference was between Wenzhounese (the southernmost Wu dialect) and all other dialects.