Data from the U.S. Census Bureau show that there are 76.4 million baby boomers.

There were actually a total of 76 million births in the United States from 1946 to 1964, the 19 years usually called the “baby boom.” Of the 76 million baby boomers born, nearly 11 million had died by 2012, leaving some 65.2 million survivors. However, when immigrants are included (the number of people coming into the United States from other countries, minus those moving the other way), the number grows to an estimated 76.4 million because immigrants outweighed the number of baby-boomer deaths. The flow of immigrants greatly increased after passage of the Immigration Act of 1965, just as the baby boom was ending.

So one can use the figure 76.4 million (or round it down to 76 million) to approximate the number of baby boomers living in the U.S. today. But keep in mind that of the 76 million babies were born in the United States during the baby-boom years (1946 to 1964), only 65.2 million of those babies were still alive in 2012, and the baby-boom age group (ages 50 to 68 in 2014) stood at 76.4 million in 2012 with immigrants included in the count.

These 76.4 million baby boomers represent close to one-quarter of the estimated 2012 U.S. population of 314 million. The choices they make about whether to retire or continue to work will have profound implications for job openings and Social Security spending. According to American Community Survey data, about 68 percent of baby boomers were still in the labor force (including Armed Forces) in 2012.

The Census Bureau currently projects that the baby-boom population will total 61.3 million in 2029, when the youngest boomers reach age 65. By 2031, when the youngest baby boomers reach age 67 (the age at which persons born in 1964 can receive full Social Security benefits), the baby-boom population is projected to be even lower, at 58.2 million.

The aging of the baby boomers is creating a dramatic shift in the age composition of the U.S. population. Projections of the entire older population (which includes the pre-baby-boom cohorts born before 1946) suggest that 71.4 million people will be age 65 or older in 2029. This means that the elderly ages 65 and older will make up about 20 percent of the U.S. population by 2029, up from almost 14 percent in 2012.