The article reports, "Mr Angel also finds that almost every city is becoming less dense. In 1920 Chicago squeezed 59 people into each hectare of land; now, by h

The article reports, "Mr Angel also finds that almost every city is becoming less dense. In 1920 Chicago squeezed 59 people into each hectare of land; now, by his reckoning, it manages just 16. The urbanised area of Mexico City is about half as densely populated as it was in 1940. Beijing’s population density has collapsed from 425 people per hectare in 1970 to just 65 people per hectare, or about the same as Chicago at its most crowded." That's certainly true where I live. The city that defines my metropolitan area had its peak population during my lifetime the year I was born, and has been losing population each year since until quite recently. Now the city is regaining a bit of population, and some of the inner-ring suburbs where I grew up (but not all of them) have embraced "new urbanism" and are as densely populated as they have ever been, but even many of the inner-ring suburbs are losing population, while the metropolitan area continues to grow as the children who grew up in the inner ring now bring up their children in bigger houses on bigger lots even farther away from the city. This is generally happening everywhere as countries reach a certain level of economic development. The story of Taiwan, the other country where I have lived long-term, was leaving the countryside for cities during my childhood, but there too (in a national context of birthrates below replacement, and thus an eventually declining population) the core cities are beginning to empty out as the surrounding suburban cities grow, and housing development is spreading up hillsides and into other areas where there is more space for yards and larger houses for ever-smaller households.