In its first results since its insurance unit CEO was fatally shot in New York City, UnitedHealth Group reported Thursday weaker-than-expected fourth-quarter revenue, prompting its shares to fall in early morning trading despite quarterly profit beating projections.

In his first public comments since one of his executives was shot to death, UnitedHealth Group CEO Andrew Witty said the healthcare system “needs to function better.”

UnitedHealth posted a better-than-expected fourth-quarter profit, but a nagging rise in medical costs and care utilization surprised Wall Street.

UnitedHealth Group has reported quarterly profits of $5.5 billion after tax in its first earnings release since the killing of UnitedHealthcare CEO Brian Thompson in New York City, which sparked a wider debate about the cost of health insurance and medication for the American public.

UnitedHealth beat fourth-quarter earnings forecast, though revenue fell short and medical costs ran high, hitting the Dow Jones component.

UnitedHealth Group Inc. reported fourth-quarter profit that surpassed Wall Street’s expectations in its first financial statement since a top executive was killed in New York last month.