Rhythm Technologies provides wearable biosensor devices to detect and monitor heart arrythmias. On December 2, 2020, iRhythm issued a press release stating that new Centers for Medicare and Medicaid Services (CMS) physician fee guidelines would change how payments for its Zio XT remote cardiac monitoring services would be calculated. On this news, IRTC shares dropped approximately 20%. Then on January 29, 2021, a Baird research analyst noted that Medicare Administrative Contractor rates affecting heart monitors are way lower than those published in the Medicare Physician Fee Schedule. On this news, IRTC shares closed down approximately 33%, wiping out billions of dollars in market capitalization.