On the demographic trend the natural factor has always had very strong effects, and in particular the climatic elements are responsible not only for the floods (and therefore for famines and even very large population decreases), for the progressive migrations towards S, during periods of accentuated aridity. Over the centuries there have been very alternating demographic developments, with sudden increases in the phases of well-being and equally frightening decreases in those of crisis, so much so that dynastic wars, floods and pestilences seem to have periodically imposed themselves as self-regulating factors, rebalancing the man-environment relationship, while the serious situation of China at the end of sec. 19th and early 20th century can also be considered determined by the exceptional demographic growth, due to the lowering of the mortality rate. In the middle of the century. XVIII it seems there were 165 million residents in the country, which became 300 million at the end of the same century; the cause of the first strong increases is attributed in large part to the introduction in southern China of corn and potato crops, which solved serious food problems. Subsequently, however, the demographic increase, given the high mortality, probably never exceeded 0.75 ‰. But the birth rate was very strong and so at the beginning of the twentieth century, with the improvement of health conditions, the increase underwent exceptional pressures and this was confirmed by the first census, carried out in 1953: contrary to the evaluations, which in 1950 gave a population of 488 million, the results were 580.6 million (excluding Taiwan).
According to Pharmacylib, the growth of the Chinese population slowed down significantly between the second half of the 1970s and the first half of the 1980s (when the average annual growth rate had fallen to 1.3%, compared to 2.4% in the previous decade), a new acceleration (+ 1.9%, on average) in the period 1986-89 and subsequently a certain stabilization, settling, in the period 1994-98, around 1%. The birth rate in the early 2000s (1.34% according to estimates referring to 2007) is largely lower than the Asian and world average, also as a result of the family planning campaigns conducted by the communist regime, which also led to dramatic consequences on abortion and even infanticide (mostly at the expense of female babies).
The first massive campaign for birth limitation was launched in 1957, when the positive and relatively rapid decline in mortality then, coupled with a much slower decline in birth rates, began to cause major alarms. Opposing trends emerged as early as 1958, but the new demographic growth of the 1970s led to the reactivation of family planning measures (legislation on compulsory abortion, economic sanctions for families with more than one child). In the Eighties these were then again attenuated due to the substantial achievement of the necessary conditions for the stabilization of the population. The mortality rate, given the youth structure of the population, remains low (7.1 ‰ according to estimates referring to 2012), practically unchanged since the 1980s. Life expectancy averaged 76.5 years for women and 73.9 years for men. The composition by sex of the Chinese population still sees a slight numerical preponderance of males, a consequence of the traditional preference of families for male children (for economic-working reasons), which has often been added to the anti-demographic policy of the regime. The age structure denotes a composition of the population that is still remarkably young: although the country is approaching demographic maturity and the age pyramid, still broadly based in the 1980s, is now closer to the “spindle” form than to that of a real pyramid, however the numerical dominance of the productive age groups continues to represent an important resource for the country’s economy. Growth rates, however, differ strongly from region to region. In the urbanized and industrialized coastal regions, population growth would have stopped for some time, were it not for immigration, which resumed massively in the 1980s and which is the cause of a sharp increase in the urban population.