Nearly one in five U.S. Millennials surveyed by BNY Mellon say they receive no financial information from their workplace or educational establishment, and nearly half admit to relying on a blind guess to estimate what they’ll need for a retirement fund.

The global survey, “Generation Lost: Engaging Millennials with Retirement Saving,” finds about one-fifth (19%) of Millennials in the U.S. do not receive any information about financial matters through their workplace or educational establishment, compared with 46% of Millennials from all respondents in other countries.

Nearly half (46%) of Millennials estimate the size of the fund they will need for retirement by taking a “blind guess” rather than basing it on industry data, and 42% say they take an “educated guess.”

A combination of factors, including demographic, political and macro-economic trends, mean that many Millennials face a less comfortable retirement than their parents and their grandparents, BNY Mellon notes. While U.S. Millennials said they received more information from their workplaces about retirement savings than respondents in other countries, they also said they were not well informed about how much money they need to fund their retirements. The survey indicates Millennials’ lack of financial understanding seems to stem from a lack of education and information more than it does from a lack of interest.

Millennials are squeezed on a number of fronts, says Paul Kelly, a graduate from Cambridge Judge Business School and joint lead researcher for the study. “High student debt, low job security and low global growth mean Millennials face a different set of financial challenges than the Baby Boomers and Generation X.”

According to the BNY Mellon survey, 91% of U.S. Millennials want to be told the “stark reality” of their post-retirement finances.

“Millennials say they want more meaningful engagement with insurers and other financial services providers and to be told the truth about how poor they may be in retirement if they do not start saving early. They are ready to hear more confrontational, honest and realistic messages about the challenges they face in providing for their retirement,” says Vincent Pacilio, global head of the insurance client segment at BNY Mellon.

“Young people need regular engagement through multiple channels if they are to be equipped to deal with the challenges they face and provide for their own retirement,” suggests Sadia Cuthbert, head of business development at Cambridge Judge Business School, a co-author of the study. And financial providers have to start marketing to Millennials in ways they want to be marketed to, and with the products they are interested in, adds John Buckley, global head of Corporate Social Responsibility at BNY Mellon.

Other findings of the survey include that U.S. respondents would allocate 39% of their portfolio to investment vehicles that adhere to socially responsible investing (SRI) factors, and 57% of U.S. Millennials would save more if their pension allowed multiple lifetime withdrawals.

“Generation Lost: Engaging Millennials with Retirement Saving,” by BNY Mellon with Cambridge Judge Business School, University of Cambridge, surveyed 1,253 Millennials (born between 1980 and 2000) between July and September in Australia, Brazil, Japan, the Netherlands, the U.K. and the U.S.