Correct hyphenation of age groups (18-25-year-olds / 18- to 25-year-olds / 18 to 25-year-olds)

As the title suggests, I’d like to ask your opinion on the correct way (or most common/recommended way) to write about different age groups. Let’s imagine you have a table showing several age groups of adults such as 18-25, 26-40, 41-60 etc.

I’ve found several different sources using different variations and cannot find a reliable source that confirms if one or all three are acceptable:

18-25-year-olds

18- to 25-year-olds

18 to 25-year-olds

Personally I’ve always used the first way, which seemed natural, but on finding the other ways I am now unsure. Thank you for anyone that can give their opinion or cite a source to confirm things.

Also, what other ways of writing about different age groups are there?

people who are 18-25 years old
people aged 18 to 25
those aged 18-25
people 18-25 years of age
people 18 to 25 years old
the 18-25 age group

Any other variations you can suggest?

Thanks in advance.