A majority of baby boomers and Generation X workers and millennials do not know how much they need to save for retirement, according to a recent survey by the Limra Secure Retirement Institute.

Sixty percent of boomers (born between 1946 and 1964) and Gen Xers (born between the mid-1960s and mid-1980s) and 70% of millennials (born between the mid-1980s and mid-2000s) are in the dark about the amount of savings they will need, Limra says.

More than half of the boomers surveyed have less than $100,000 in retirement savings, and more than one-third have less than $25,000, the survey of 2,000 working Americans shows.