That's fair, I would be fine if that study looked at 30 year olds. A specific age makes sense. A range a decade long is statistical mud.^
30 years old is of huge cultural importance in Asia
Sheng nü - Wikipedia
en.wikipedia.org
Unmarried and Over 27? In China, That Makes You a “Leftover Woman”
Sheng nu refers to any urban, professional woman over the age of 27 who is still single.www.vogue.com