Up until the latter portion of the 20th century in OECD countries, and contemporarily in developing countries around the word, young people made the transition from adolescence to young adulthood around or by the age of 22, when they settled into long-lasting, obligation-filled familial and occupational roles [REF].
Among OECD countries, there is a general "one size fits all" model in regards to emerging adulthood, having all undergone the same demographic changes that resulted in this new stage of development between adolescence and young adulthood.