As a result of these and other changes, during the second half of the twentieth century industry decamped from many first-world central cities in search of lower wages, looser environmental standards and wide-open spaces in northern suburbs, rural towns and international “free trade zones.” New York City is an extreme but telling example: from the 1950s to the 1990s, the city lost 750,000 manufacturing jobs while its land values soared from $20 billion to $400 billion.