© NewsFrom 1990 to 2010, the percentage of workers 65 and older staying in the job market rose for both women (from 28.2 percent to 43.8 percent) and men (52.5 percent to 65.3 percent).
For a growing number of Americans, there may never be such a thing as real retirement.

"The market is filled with people who are petrified of the idea of retiring because they might not have the funding to afford retirement,"'s Melissa Doran Rayer, whose company provides financial planning services and created a data chart to show how retirement trends are shifting, told Yahoo News in a recent interview.

From 1990 to 2010, the percentage of workers 65 and older staying in the job market rose for both women (from 28.2 to 43.8 percent) and men (52.5 to 65.3 percent).

Interestingly, those trends have occurred in the 35-plus years since the Revenue Act of 1978 was passed, allowing workers to invest tax-deferred savings in 401(k) plans.

There have also been broad cutbacks to pensions across the U.S. A recent analysis found that more than 20 million American workers could have their retirement threatened from pension mismanagement.

The percentage of companies offering pension plans has also declined, as have the average retirement contributions in corporate 401(k) plans. In February, AOL's CEO Tim Armstrong faced wide criticism for his plans to both alter and scale back company 401(k) contributions.

There's also the risk that people will plan poorly for their retirement, choosing either to retire too early or to spend too much when they need to be living on a more modest budget.

For example, a new online test about Social Security, which found that about only 5 percent of respondents correctly answered a set of basic questions about when and how to best use their retirement funds.

"There are two or three key mistakes - people planning for too early a retirement or too lavish a retirement," Tash Elwyn, president of Raymond James & Associates, told USA Today.

"It might mean that you're working part-time or that you're starting a new business," Doran Rayer said. And for some, starting a new business is obviously a positive choice. But she said it can also be the only option for some older workers struggling to find a place in a workforce that has largely left them behind.

"Going forward, it's not so much retirement but financial flexibility," she said. "It means the freedom to make decisions for themselves about the types of jobs they take on. Maybe not how much their W-2 reads at the end of the year, but things they want to be doing."