Moderna's (MRNA -20.84%) sales are slowing down, and Moderna stock is going down -- a lot.The coronavirus vaccine maker's shares plunged 21.2% through 10:20 a.m. ET Monday after it updated investors on its 2024 performance and released new guidance for 2025. Moderna in 2024...and 2025Moderna estimates it ended 2024 with somewhere between $3 billion and $3.1 billion in product sales as it shifted its business toward treating COVID-19 as an "endemic" illness rather than a novel and spreading pandemic. CEO Sté ...