Historians are now turning to local gazetteers of Ming China for clues that would show consistent growth in population. Using the gazetteers, Brook estimates that the overall population under the Chenghua Emperor (r. 1464–87) was roughly 75 million, despite mid-Ming census figures hovering around 62 million. While prefectures across the empire in the mid-Ming period were reporting either a drop in or stagnant population size, local gazetteers reported massive amounts of incoming vagrant workers with not enough good cultivated land for them to till, so that many would become drifters, conmen, or wood-cutters that contributed to deforestation. The Hongzhi and Zhengde emperors lessened the penalties against those who had fled their home region, while the Jiajing Emperor (r. 1521–67) finally had officials register migrants wherever they had moved or fled in order to bring in more revenues.