The percentage of employers with grandfathered healthcare plans continues to dwindle, according to a survey released Thursday.

Just 27.3% of employers responding to an International Foundation of Employee Benefit Plans survey said their primary healthcare plan has grandfathered status this year, down from 34.3% last year and 44.6% in 2011.

Under the Patient Protection and Affordable Care Act, grandfathered plans are exempt from certain requirements, such as providing full coverage of preventive services.

But to maintain grandfathered status, a health plan can't increase coinsurance requirements or boost the percentage of the premium paid by enrollees by more than 5 percentage points, among other requirements.

Because such health plans can make only limited cost-sharing changes, “maintaining grandfathered status can be a challenge for employers,” according to the survey.

And grandfathered plans will continue to decline, according to the foundation. Some 2.5% of respondents said they expect their primary health care plan to lose grandfathered status this year, while 31.3% said they expect their primary plan to lose grandfathered status in 2014.

The survey is based on responses from 966 benefits professionals.

Grandfathered health plans dwindling: Analysis originally appeared on Crain's Business Insurance.