surplus labor in rural areas due to higher average fertility rates, and improved living conditions all play a role in contributing to the flows of migrants from rural to urban areas. Approximately, 250 million rural migrants now live in cities with 54% of the total Chinese population living in urban areas. England and Wales A focus by landowners on efficient production led to the enclosure of the commons in the 16th and 17th centuries. This created unrest in rural areas as tenants were then unable to graze their livestock. They sometimes resorted to illegal means to support their families. This was followed, in turn, by penal transportation which sent offenders out of the country, often Australia. Eventually, economic measures produced the British Agricultural Revolution. Germany Middle ages Rural flight has been occurring to some degree in Germany since the 11th century. A corresponding principle of German law is Stadtluft macht frei ("city air makes you free"), in longer form Stadtluft macht frei nach Jahr und Tag ("city air makes you free after a year and a day"): by custom and, from 1231/32, by statute, a serf who had spent a year and a day in a city was free, and could not be reclaimed by their former master. German Landflucht Landflucht ("flight from the land") refers to the mass migration of peasants into the cities that occurred in Germany (and throughout most of Europe) in the late 19th century. In 1870 the rural population of Germany constituted 64% of the population; by 1907 it had shrunk to 33%. In 1900 alone, the Prussian provinces of East Prussia, West Prussia, Posen, Silesia, and Pomerania lost about 1,600,000 people to the cities, where these former agricultural workers were absorbed into the rapidly growing factory labor class; One of the causes of this mass-migration was the decrease in rural income compared to the rates of pay in the cities. Landflucht resulted in a major transformation of the German countryside and agriculture. Mechanized agriculture and migrant workers, particularly Poles from the east (Sachsengänger), became more common. This was especially true in the province of Posen that was gained by Prussia when Poland was partitioned. The Polish population of eastern Germany was one of the justifications for the creation of the "Polish corridor" after World War I and the absorption of the land east of the Oder-Neisse line into Poland after World War II. Also,