Why People Over 50 Say Ages 30–34 Were Their Most Fulfilling Years
That, the European paper suggests, goes against previous “U-shaped” theories of happiness across age. Some studies state that SWB is high in adulthood, stays roughly level throughout adulthood, and peaks again in older age (some research says this falls sharply after 75).
Article source: https://www.huffingtonpost.co.uk/entry/happiest-life-age_uk_69a01b61e4b0ec14093d82b6