The rise of new emperors and new factions diminished such extravagances; the capture of the Zhengtong Emperor during the 1449 Tumu Crisis ended them completely. The imperial navy was allowed to fall into disrepair while forced labor constructed the Liaodong palisade and connected and fortified the Great Wall of China into its modern form. Wide-ranging censuses of the entire empire were conducted decennially, but the desire to avoid labor and taxes and the difficulty of storing and reviewing the enormous archives at Nanjing hampered accurate figures. Estimates for the late-Ming population vary from 160 to 200 million, but necessary revenues were squeezed out of smaller and smaller numbers of farmers as more disappeared from the official records or "donated" their lands to tax-exempt eunuchs or temples. "Haijin" laws intended to protect the coasts from "Japanese" pirates instead turned many into smugglers and pirates themselves.