Democrats like Congresswoman Alexandria Ocasio Cortez think they are mobilizing youth in a “wave of the future” moment. But that’s not how the world is going. In this video, the statisticians at The Economist illustrate what the future will really look like…
The pyramid is a traditional way of visualizing and explaining the age structure of a society. If you draw a chart with each age group represented by a bar, and each bar ranged one above the other, youngest at the bottom oldest at the top, and with sexes separated, you get a simple shape.
In 1970 that shape was a pyramid because the largest segment of the global population was the youngest. 0-5 years old comprising 14% of the total, followed by the next youngest 6-10 with 13% and so on in regular increments until about 85 years old - there were so few people that the shape vanished into a point.
The pyramid was characteristic of human populations pretty much since the day organized societies emerged - with life span short a mortality high, children were always the most and old people the least numerous group.
A population chart of England in 1700 looks like a pyramid but now look at the chart of the global population in 2015. It looks more like the Dome of the Capitol building in Washington DC than something you find along the Nile. Young children are still the largest group but now make up only 10% of the population and those above them are almost as big with 9.5. The angle of the slope changes most markedly only after the age of about 40.
In 1970 the youngest had not only been the largest but also the fastest-growing section of the population but between 1970 and 2015 the population age 0-19 grew by only 42% whereas the population age 20 to 39 rose by a hundred and twenty eight percent.
This group added almost twice as many people to the overall numbers than the group age below 20. There are also now over 50 million people above 85 so the dome of 2015 has a spike. In 1970 to 2015 the dominating influence upon the global population was the fertility rate - that's the number of children a woman can expect to bear during her lifetime. It fell dramatically over the period meaning that the world shifted from having larger to smaller families. In 2015 to 60 the biggest influence upon the population will be aging. Small families are already the norm. The fallen fertility is slowing down and now everyone's living longer than their parents, dramatically so in developing countries.
So by 2060 the dome will have come and gone and now the shape of the population looks more like a column or perhaps an old-fashioned beehive. It's a little fatter near the bottom and curves in at the top but up to the age of about 50 the generations are of almost equal size and the shape has vertical sides.
The size of the Earth's population is still rising. From 7.2 billion 2015 to 9.5 billion in 2060. But according to calculations by Emi Suzuki and Wolfgang Fengler of the World Bank, two-thirds of the extra 2.2 billion people will come from the older age groups those aged 40 to 59 and between 60 and 79 - not from the younger.
The increase in the last oldest segment is a specially marked. Between 2015 and 2016 the number of 60 to 79 year olds will double to 850 million. That's more than four times the increase in the number of children and teenagers which will rise by only 200 million or 8%.
The numbers of the oldest people of all, those above 85, will rise at the fastest rate by 281% in 2015 to 60 but from a much lower base so they do not add as many people to the total. For all of history humans have lived in societies dominated in numbers at least by children. By 2060 children will be no more numerous than any other age group.
The year 2015 was roughly the halfway point in this astounding transformation.