Use the format “aged [age] years”

aged nine years

Use the format “aged [age] to [age] years”.

aged 10 to 11 years

Include the months or weeks for ages under a year.

aged nine weeks

If you refer to ages as “[age]-year-old”, include the hyphens.

16- to 24-year-old men

Write decades as an age as numerals.

women in their 40s

Limits for age restrictions should use “aged [age] years and over” or “aged under [age] years”. Do not use the plus sign.

aged 75 years and over

aged under 18 years