NEW YORK (MainStreet) -- Considering so many Americans rely on Social Security for a good piece of their retirement funding, you'd think retirees would know more, or want to know more, about maximizing their Social Security benefits.

For example, a 2015 Fidelity Investments study states that 60% of couples and 49% of Baby Boomers don't have any idea how much their Social Security benefit might be, "even though the information is readily available on the Social Security website."

That's just for starters.

A separate study from the American Association of Retired Persons reveals some additional, eye-opening statistics on what Americans "don't know" about Social Security.

For instance . . .

- Only 9% of U.S. consumers say they are "very knowledgeable" about how their Social Security benefits are calculated.

- Only 1% of U.S. certified financial planners say their clients are "very knowledgeable" about their Social Security benefits.

- Only 39% of Americans think Social Security will comprise at least 50% of their income, even as AARP reports "that as Americans age, their reliance on Social Security increases significantly, with nearly six in ten Americans relying on Social Security for at least half of their retirement income after they reach 80 years of age."

- 83% of Social Security recipients "overestimated or underestimated the amount of money they would receive if they waited to become beneficiaries at their full retirement age."

- 39% of American adults AARP surveyed didn't know that 62 is the age they can first claim early Social Security retirement benefits.

Social Security experts say future retirees are using some fuzzy math - and fuzzy logic - in figuring out when to start taking Social Security, and in many cases that mindset is working against them, financially.

Andrew McFadden, who teaches Social Security workshops and classes in Fresno, Calif., has a front-row seat on how many Americans get Social Security wrong. "One big misconception is that Social Security is going bankrupt," he says. "Actually, it's not. The surplus in the OASI (Old Age and Survivor Income) trust fund is expected to run out in 2035."

There's a negative effect to that skewed line of thinking. "Because of this misconception, people believe that they need to claim benefits as early as possible -- age 62 -- to avoid getting snubbed by Social Security," McFadden says. "As a result, they collect less benefits over their lifetimes than they could have."

If you do take Social Security proceeds out early, as McFadden states, know that you're leaving money on the table after you walk away.

"Retirees may not understand how much can be gained by delaying the year they begin taking Social Security," says Sean Condon, a financial advisor with Windgate Wealth Management in Chicago. "Every year retirees delay Social Security after full retirement age -- 66 years old if born between 1943 and 1954, 67 years old if born in 1960 or after -- their annual benefit increases by 8%. Compared to potential investment returns, this guaranteed return can be very favorable."

Another Social Security workshop leader, Sev Meneshian, of Chicago-based Public Retirement Planners and a professor of retirement planning at Northwestern University, says there is big confusion among consumers about lump sum payments. "I just did a Social Security workshop, and not one of the 50 attendees knew you can get a lump sum payment for deferred earnings," Meneshian says. "The amount can be over $120,000."

Confusion plays a role, too, Meneshian says. "For instance, married couples have over 1,500 ways to file for benefits, oftentimes putting over $50,000 more in their pockets by picking a superior filing strategy," he says. Getting professional financial advice can break those options down for you, Meneshian adds.

With retirement funding options so scarce for many Americans, not knowing what Social Security offers (and when) can lead to big problems down the path into retirement. "Social Security can be viewed as an annuity, and for many, this is the only guaranteed lifetime income they will have, it is important to make the right decision," says Chris Blackmon, a financial planner at Biggers Blackmon Wealth Management in Atlanta.

But without the right data, that decision might cut into your retirement income, and leave you wondering one day why you weren't paying attention to Social Security - until it was too late.