How much income is enough for a comfortable life between different age 20,30,40,50,60,70,80?

Everyone is different, i can only say

Never enough because you need to know what is comfy

Different people have different needs and wants, so it is hard to say how much is enough per person as a general estimation. Some people have the YOLO mindset and want to experience good food, luxury travels, comfy lifestyle and will find ways to support their lifestyle. Someone has ever mentioned the cost of living is Spore is actually not that high if we are happy with a simple life, it is our lifestyle that makes it costly.

Difficuly to put a number to it as it depend on one's lofestyle, life circumstances, etc.