Thanks to collapsing oil prices, inflation has been flat — and that means it’s looking more and more likely that retirees won’t see a cost-of-living increase in their Social Security checks come January.

And while that will be tough enough — especially on retirees who are already struggling to get by on those Social Security checks — the ones who will really be feeling the effects are those in higher income brackets, who will likely see their checks go down as a result of higher Medicare Part B premiums.

The latest annual report from the Social Security trustees is projecting no COLA for 2016, because the price of oil has fallen so much it’s undercut all the other expenses considered when determining how much seniors get to live on.

But it is projecting a big increase in Medicare premiums, which is going to hurt no matter how you look at it.

COLA is decided by evaluating third-quarter inflation in terms of the Consumer Price Index for Urban Wage Earners and Clerical Workers.

But seniors have a heavier allocation, if you will, of their retirement checks to the health care sector, since they’re paying not just Medicare premiums but also whatever out-of-pocket costs might have to be met in treating various illnesses, injuries, or conditions.

And since inflation in the health care sector has been running steadily ahead of the economy overall, that means that seniors are paying more — but the fact is not recognized by the standards that assess how much their cost of living actually is.

An alternative measure of what elders spend, the Consumer Price Index for the Elderly, would take into account the expenses unique to seniors or that dominate their budgets — but of course that’s not the one used to determine how much they’ll get in their checks.

But here comes the real bad news: because of how much health care costs are increasing, it’s looking as if some Medicare premiums will rise by as much as 52 percent.

While not all seniors are going to see their benefit checks go down — most are protected by a “hold harmless” provision in the way the system is structured, so that premium hikes can’t actually cut benefits for the majority of recipients — about 30 percent are exempt from that “hold harmless” provision and will be hard hit.

So who’s going to be hurt?

  • Enrollees in Medicare who aren’t yet collecting Social Security benefits because they chose to delay enrollment.

  • People who enroll in Medicare next year.

  • High-income seniors, who aren’t protected by the “hold harmless” provision. (Those high-income seniors are already paying more for their Part B — outpatient services — and Part D — prescription drug — coverages.)

Sad news on the 80th anniversary of Social Security indeed.

See also:

Annuities critical in retirement planning

An inflection point: The current state of Social Security

The new debate about Social Security