Sinologist Historians still debate the actual population figures for each era in the Ming Dynasty. The historian Timothy Brook notes that the Ming government census figures are dubious since fiscal obligations prompted many families to underreport the number of people in their households and many county officials to underreport the number of households in their jurisdiction. Children were often underreported, especially female children, as shown by skewed population statistics throughout the Ming. Even adult women were underreported; for example, the Daming Prefecture in North Zhili reported a population of 378 167 males and 226 982 females in 1502. The government attempted to revise the census figures using estimates of the expected average number of people in each household, but this did not solve the widespread problem of tax registration. Some part of the gender imbalance may be attributed to the practice of female infantcide. The practice is well documented in China, going back over two thousand years, and it was described as “rampant” and “practiced by almost every family” by contemporary authors. However, the dramatically skewed sex ratios, which many counties reported exceeding 2:1 by 1586, can’t likely be explained by infanticide alone.
The number of people counted in the census of 1381 was 59 873 305; however, this number dropped significantly when the government found that some 3 million people were missing from the tax census of 1391. Even though underreporting figures was made a capital crime in 1381, the need for survival pushed many to abandon the tax registration and wander from their region, where Hongwu had attempted to impose rigid immobility on the populace. The government tried to mitigate this by creating their own conservative estimate of 60 545 812 people in 1393. In his Studies on the Population of China, Ho Ping-ti suggests revising the 1393 census to 65 million people, noting that large areas of North China and frontier areas were not counted in that census. Brook states that the population figures gathered in the official censuses after 1393 ranged between 51 and 62 million, while the population was in fact increasing. Even the Hingzhi Emperor (ruled in 1487-505) remarked that the daily increase in subjects coincided with the daily dwindling amount of registered civilians and soldiers. William Atwell states that around 1400 the population of China was perhaps 90 million people, citing Heijdra and Mote.
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 Chenguah Emperor (ruled in 1464–1487) 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 Hingzhi and Zhendhe emperors lessened the penalties against those who had fled their home region, while the Jiajing Emperor (ruled in 1521–67) finally had officials register migrants wherever they had moved or fled in order to bring in more revenues.
Even with Jiajing’s reforms to document migrant workers and merchants, by the late Ming era the government census still did not accurately reflect the enormous growth in population. Gazetteers across the empire noted this and made their own estimations of the overall population in the Ming, some guessing that the population had doubled, tripled, or even grown fivefold since 1368. Fairbank estimates that the population was perhaps 160 million in the late Ming Dynasty, while Brook estimates 175 million, and Ebrey states perhaps as large as 200 million. However, a great epidemic that entered China through the northwest in 1641 ravaged the densely populated areas along the Grand Canal; a gazetteer in northern Zhejiang noted more than half the population fell ill that year and that 90% of the local populace in one area was dead by 1642.