A whopping three quarters of Americans fail a quiz on how tomake their retirement dollars go far enough to seethem all the way through retirement, although they think they knowwhat they're doing; 61% of respondents indicate they have highlevels of retirement income knowledge.

But—and it's a big but–among those who claim to be highlyknowledgeable, only 33% could pass a retirement income quiz.

That's according to The American College of Financial Services,whose RCIP Retirement Income Literacy quiz revealed frighteninggaps in workers' knowledge and understanding of retirement income—aclear indication that both plan sponsors and advisors should heedthe obvious need for more and better education.

Not only are Americans clueless when it comes to stretchingthose hard-saved dollars, the study finds that older Americansaged 60–75 with at least $100,000 in assets fail to know enough,for their own good, about such topics such as paying for long-termcare expenses, investment considerations or strategies forsustaining income throughout retirement and life expectancy.

Less than 1%, in fact, managed to score an A on the quiz, while74% got an F.

Just 5% managed a B, 8% a C and 13% a D. And demographics made adifference, even with the dismal percentages displayingunderstanding of essential retirement issues.

Financial literacy rates varied substantially between men andwomen, the college educated and the noncollege-educated and betweenwealthier and less wealthy respondents.

Only 17% of women, for instance, passed, compared with 35% ofmen; 49% of respondents with over $1 million in assets passed asopposed to 20% of respondents with below $1 million in assets and40% of those with a graduate degree or more passed, compared withjust 9% of respondents without a college degree who passed.

And they're not very savvy about strategies to make thosedollars go farther, with just 33% understand that it is moreeffective to work two years longer or defer Social Security for twoyears than to increase retirement contributions by 3% for fiveyears just prior to retirement.

And only 45% grasp the concept that a life annuity can protectagainst life expectancy risk, while 38% of participants in thesurvey understand the “4% rule” that counsels against taking morethan 4% annually from a retirement account lest it be depleted.

And when it comes to long-term care, the picture is evengrimmer, with 82% of respondents not expecting that most olderAmericans will need LTC at some point in their lives.

They're also not knowledgeable about critical facts having to dowith LTC itself: only 33% know that Medicaid pays for the majorityof LTC expenses provided in nursing homes, while just 30% know thatfamily members—not nursing homes, assisted living facilities, orhospitals—are the ones providing the majority of LTC costs.