Providers aren’t just being accused of coding therapy patients in higher payment categories than ever before. The charge is being backed by hard numbers in a recent memorandum from the Centers for Medicare & Medicaid Services.

More than 50% of SNF Medicare Part A billed days of service in 2013 were in the Ultra-High Rehabilitation category. That’s up from 44.8% just two years earlier. All other therapy billing categories remained steady or dropped.

“The percentage … has not only increased, but done so rather steadily,” authors noted in the “Observations on Therapy Utilization Trends” memo. It was issued with recently proposed SNF Medicare rates for 2015.

Providers also are commonly delivering “just enough” therapy to reach into higher pay categories, researchers found.

CMS said it will continue to monitor billing patterns and might adjust policies accordingly in the future.