Core Viewpoint - Cigna Group's shares fell by 17% following a warning about declining profit margins in its pharmacy-benefit-services division over the next two years [1] Summary by Relevant Sections - **Company Performance** - Cigna Group's stock experienced a significant drop of 17% on Thursday [1] - **Profit Margins** - The company indicated that profit margins in its pharmacy-benefit-services division are expected to decline in the upcoming two years [1]