Economy of the last 100 years resumed Gold and Purchasing Power

This is just a simple observation of what happened with Gold in the last 100 years.

Here I show some important economic events highlighting the purchasing power with a red line.

When you open a GOLD chart, you can look at the trend and think that it had a very strong bull market during the last century. And you are right, it had a very strong one, but against your currency.
In reality, the value of GOLD has not increased that much. The purchasing power chart speaks by itself.

Most central banks are private entities that are not controlled by the governments of the countries.

From the chart, I can deduce that In a bank, you can keep the money, but not it's value.

What do you think about central banks, is a fair system? Write it in the comments.

If something of what I wrote here is not correct, please let me know.