As you grow as a person, 20s for eg, is it really young?

[Jibralta]

If in the likely future, people are 150 years old, would you call a 60 year old citizen young?

 

60/150 = 40%

 

So, yes 60 would be youngish. But 38 would be the new 20 (young). 75 would be middle aged.