I noticed that people always say that the elephant in the room is population. Then they go a bit embarrassed and we start talking about football again. It’s not the elephant in the room. It’s the people in the room which are the problem. I tried to get a feel for some numbers.

Say there are 7 billion people on the world. 130 million are born every year. 60 million die every year. That’s an increase of 70 million a year.

If that goes on for 40 years, then the population increases by 40 x 70 = 2.8 billion. Call it 3 billion. So the world’s population goes to close to 10 billion.

What would it take to get the population down to, say, 3 billion by 2050?

That is a fall of 4 billion over 40 years, so a fall of 100 million per year. If 60 million people die a year you can’t get a fall of 100 million per year.

So let’s say that the target is 3 billion by 2100 then.

A fall of 4 billion over 90 years means a fall of 44 million a year.

As 60 million die each year, in order to achieve a fall of 44 million a year, we would have to go from 130 million births a year to 16 million births a year. So almost nine out of ten people who would otherwise have a kid would have not to have one.

Let’s say that there are 50 million births a year.

If there are 60 million deaths and 50 million births, then there would be a decline of 10 million people per year. About 1 ½ thousandths. At that rate by 2050 there would be 6.6 billion people (40×10 million fewer) and by 2100 there would be 6.1 billion people (deduct a further 500 million).

That’s some numbers without judgmental overtones.