According to one study, nearly 60 percent of Americans with frequent flyer miles admit they don’t know how airline reward programs work.

The Economist estimates there are 17.5 trillion unused miles worldwide. That’s enough to fly around the world more than 116 million times.

Many major airlines, such as American Airlines, are changing how we earn and redeem miles.

This week American Airlines is joining Delta and United by moving away from miles based on distance flown to miles earned on ticket price.

In a statement released to CBS This Morning, American Airlines said:

“We are always seeking to be the best in the business and to provide our best customers with the best access to our best benefits. With the change to a revenue-based award program later this year, we are closing undeniable competitive gaps for our best customers and laying the foundation for the future of the program.”

The fare-based mileage system is designed to drive additional revenue to the airlines, especially for the full fare first and business class passengers.

For everyone else, it makes it harder to earn miles. One of the results of this is a staggering number of unredeemed frequent flyer miles.

If you do the math—if 54 percent of all frequent flyer mileage is earned on the ground with credit cards—it’s easy to see how much money you’ve actually spent to get that supposed free ticket. That’s assuming the airline makes one available.​

Right now both JetBlue and Southwest have more generous redemption programs and offer more frequent flyer award seats.

In the case of Southwest, the airline offers perhaps the best frequent flyer perk. Once you earn 110,000 points (which you can earn without even flying, but by using their branded credit card), your companion flies free for a year.

Regardless of which airline, there’s a good chance you have some frequent flyer miles saved up. The last thing you want to do is simply accrue and hoard miles. They will only decrease in value.

My advice? Throw out your bucket list. Want to redeem your miles for Paris, London, or Hawaii?

Guess what? Everyone else does, too. Think 330 days out and pick a place you’ve never been—or even considered visiting—and pick that destination. You’ll have a great time, and you’ll actually be able to redeem your miles.

Watch Peter Greenberg’s report for CBS This Morning to learn more:

For more information about frequent flyer programs, check out:

• Why You Should Use Your Frequent Flyer Miles Soon
• Delta SkyMiles Devalued? Let’s Do the Math
• Getting the Most From Your Frequent Flyer Program

By Peter Greenberg for PeterGreenberg.com