The updated tally extends the scope beyond what was previously described by company Chief Executive Andrew Witty.

About 190 million Americans may have been affected by a cyberattack targeting UnitedHealth‘s subsidiary, Change Healthcare. The breach, which disrupted the company’s IT systems, resulted in the compromise of sensitive personal and medical information.

UnitedHealth Group (NYSE:UNH) disclosed a cyberattack on its tech unit last year, impacting the personal information of 190 million individuals, marking the largest healthcare data breach in U.S. history.

The attack, originally thought to have impacted about a 100 million Americans, is even larger than originally disclosed.

The cyberattack at UnitedHealth Group exposed personal information of 190 million people, leading to a $22 million ransom payment in bitcoin.