During the first half of this year, Millennials (born 1977-1994) accounted for a larger share of new-vehicle retail sales than Gen Xers (born 1965-1976), the first time this has occurred, per J.D. Power, with the former comprising 26% share of sales and the latter 24% share. Baby Boomers (born 1946-1964) are still the generational cohort buying the most new vehicles, though. Indeed, Boomers accounted for 38% share of sales during the first half of the year. Last year, J.D. Power data indicates that Baby Boomers accounted for 40% of new-vehicle retail sales, compared to 24% for Gen Xers and 23% for Millennials. (sources: J.D. Power, MarketingCharts.)