Rocket Lab USA, Inc. (RKLB) experienced a significant 24-hour plunge of 5.02% during after-hours trading on Thursday. The sharp decline followed the release of the company's fourth-quarter financial results.

Despite reporting quarterly earnings that surpassed analyst expectations, with revenue of $179.7 million beating estimates and a narrower-than-expected per-share loss of $0.09, investor sentiment turned negative. The primary catalyst for the sell-off was the announcement of a further delay for the company's Neutron medium-lift rocket program, now targeted for the fourth quarter of 2026.

The delay was attributed to a recent stage 1 tank test failure, overshadowing what the company described as a "record-breaking year" financially and operationally. Rocket Lab's strong quarterly performance and optimistic first-quarter guidance of $185-200 million in revenue were insufficient to counter investor disappointment over the Neutron setback, which has been a key component of the company's growth strategy.