Linda Searing

Sometime this year, the millennial generation – those born from 1981 to 1996 – will overtake baby boomers as the largest adult population group in the United States, according to government data analyzed by the Pew Research Center.

The number of millennials is projected to reach 73 million, aided in part by immigration, while the boomer population, born from 1946 to 1964, is expected to decline to 72 million this year as members die off. Boomers (the only generation officially given a name by the Census Bureau) peaked in size at nearly 79 million in 1999.

The aging of such a large group will continue to put pressure on the U.S. health-care system and Medicare costs. According to the Census Bureau, by 2030, when “all baby boomers will be older than age 65,” 1 in 5 U.S. residents will be of retirement age. Gen Xers – a smaller group sandwiched between millennials and boomers and now mostly in middle age – will finally outnumber boomers in 2028.