World's exponential growth

Probably the most interesting video I've seen this month and by far this week is just about the arithmetic of Ln2.
I know it sounds a little bit boring, but maths, applied with common sense and in the right way changes a simple figure into reliable data and predictions to the future.

The correct use of Ln2 provides the user the ability to predict when a figure is going to double if it grows with a constant rate, let's say e.g. 5% per year.

The arithmetic is very simple: nº years = (Ln2)/(5%) = (100*Ln2)/5 = 14 years

You can do the arithmetic in your mind easily due to 100*Ln2 = 70. Also 70/5 = 14

That means that a figure that grows 5% per year would double in 14 years.
If the growth is 7% a year, it would double in 10 years. (nº = 70/7 = 10)
If the growth rate is 10% it would double in 7 years and so on.

So, why is this so important? Let's see what's going to happen in the World in the next years.

GDP Growth rate

China and India's GDP grow at a rate of 10% per year and Brazil's GDP at a rate of 7.5%. Germany's GDP growth rate just at a rate of 3.5%.
That means, and figures and arithmetic don't lie, that China and India will double their GDP, and therefore the market value of all final goods and services produced in that countries, just in 7 years: 2019!
Brazil in 10 years: 2022! And Germany, which growth rate is the biggest in EU, at a constant rate of growth, will double in 20 years: 2032.

Population Growth rate

That's another important figure for The Earth's future. In the 80's the World growth rate was 1.9% per year (we were 5,000 million people in the World). Now we are 7,000 million people (40% more just in 25 years) and our growth rate is 1.1% per year. That means that aproximately in 2080 we'll be 14,000 million people. I know that's imposible cause there aren't enough resources for everyone so something is going to happen before 2080.



Maybe it's the WWIII, maybe is just an illness like the Black Death or the Great Famine (killing more than 300 million people in 14th century).

Fortunatly, the biggest and advanced countries in the world are reducing their birth rate and converging to small families with 1 to 2 children per woman, which will ensure the equilibrium between people and resources.

Unfortunatly, there are still some countries with more than 2 children per woman (which are experimenting the highest population and growth rates), and that tradicionally had health problems and high mortality but now, due to health care systems and medicines, the mortality rate is improving sometimes faster than we're changing those people minds about having small families.