Ah, retirement. Heavenly moments of well-deserved rest and worry-free relaxation together in the sun, on a boat or even in separate bathtubs out back on the grass.

If only.

Here’s the reality: A large number of still-working Americans are worried about having enough money to live on comfortably in retirement.

And well they should, it seems. This year for the first time since 1982, the Wall Street Journal reports, revenue from your employer and  contributions off your paychecks into the Social Security Administration will fall below expenditures. This means Social Security will have to dip into its trust fund to start paying full benefits.

That may be fine for now; the trust fund contains some $3 trillion. But those baby boomers are living longer and drawing benefits longer. And so will their kids.

By 2034, unless Congress does something (and we all know how reliable its actions are), that trust fund will be gone. Poof! Which means benefits will fall to about 75 percent of what they’re supposed to be.

And by the way, Medicare’s hospital insurance fund will be gone in eight years, down from an estimated 11-year lifespan just 12 months ago.

As a result, a dwindling number of Americans expect to have sufficient retirement income to live comfortably. Fifty-one percent feel that way, down from 54 percent last year.

Those who fear having insufficient financial resources now stands at 46 percent, up from 42 percent last year, Gallup reports.

Over the years studies have shown young people are almost universally optimistic about retirement resources. Then shortly after age 30, reality — and worry — begin to set in and anxiety grows until retirement.

The same data show that once retired, however, people are often pleasantly surprised by how far their resources go, especially once a certain frugality sets in.

About $30,000 annual household income seems to  be the cutoff. Fifty-four percent of those making less than $30,000 say they do not have enough to live comfortably. But 83 percent with incomes over $30,000 but under $75,000 say they have enough.

It might not surprise that 98 percent of those with retirement income above $75,000 say they are living comfortably.