Sometimes people ask me what I think is more important, to be rich or to be happy. Most of the time obviously the expected answer is "to be happy", and I agree with that, but I think the more interesting question would be: "What makes us happy?"
The answer to this question may strongly vary from person to person. In my case being happy means also to be free and independent, to decide myself when to sleep, when to wake up, when, where, how long and if at all to work, also where I want to live ... to be able to decide all these things myself, as well as living independently from exterior constraints, it is necessary to have enough financial resources ...

I am not one of the persons who like to be wealthy in order to live a life of luxury, I don't want to be rich just because of being rich, but nevertheless I would like to be rich because I want to be free ...

Well if that's the case, then is there some magical number we can all aim for after which diminishing returns in general contentment really start to kick in?

If at all such a "magical number" exists, one has to consider the different costs of livings in the different parts of the world as well ...

This assumed amount of money (let's say the mentioned $75,000 a year in a country like the USA) would fulfill all material needs. So maybe for most people it wouldn't increase happiness significantly to get even more money. However even if this percentile is statistically correct, it need not to be accurate for every single individual. For example it would not be enough to live as free as I described above, which for me personally is a key factor of being happy.