Earlier this year, Medicare celebrated its 50th anniversary. For a half-century, older Americans and other beneficiaries have set out each autumn to choose their Medicare coverage for the year ahead. Nearly 289,000 people here in the Seattle-Everett area are part of this annual rite of passage for Medicare beneficiaries.

Over the summer, we asked 1,000 older adults to share their perspectives on the milestones in Medicare’s evolution that have been the most meaningful as part of a survey called the Medicare Made Clear Index. Their top three milestones? The addition of coverage for preventive services and annual wellness visits was the most popular choice, selected by 17 percent of respondents. Prescription drug coverage was the runner-up, chosen by 14 percent of survey respondents, with the ability to access Medicare coverage through private health plans coming in a close third at 13 percent of respondents.

The more than 19 million Americans who were the first to enroll in Medicare in 1965 had just one simple choice to make — to sign up or not. The open enrollment experience is vastly different for today’s beneficiaries, who have many options to consider, thanks in large part to those milestones that broadened the scope of plans, benefits and services available to people enrolled in Medicare.

While the options mean that beneficiaries are able to select a plan or combination of plans that’s well-suited to their unique health and budget needs, navigating through them during the Open Enrollment Period can sometimes feel overwhelming. People should know that resources are available to make the process of shopping for Medicare coverage easier to manage. For example, the Plan Finder on www.Medicare.gov is a great tool that can help beneficiaries compare plans available in their area.

As Medicare celebrates its golden anniversary this year, I encourage beneficiaries to pay tribute to this important program by taking full advantage of the Open Enrollment Period. From now until Dec. 7, they should explore their options and choose Medicare coverage that will support their health and financial goals in 2016.

Jeff Underwood is the CEO of UnitedHealthcare Medicare &Retirement in Washington state. UnitedHealthcare serves nearly 1 in 5 Medicare beneficiaries, including nearly 279,000 Medicare beneficiaries in Washington state.

Correction: An earlier version of this commentary misstated the number of Medicare beneficiaries served in Washington state by UnitedHealthcare. The insurance carrier represents 279,000 Medicare beneficiaries in the state.