Declined

• Suffered the Titanic's fate
• Dropped sharply
• Modest Mouse "We Were Dead Before the Ship Even ___"
• Torpedoed
• What Atlantis did, presumably
• Fell gradually
• Went down like a cement block
• Plummeted
• Headed to bed?

Douglas Harper's Etymology Dictionary Word definitions in Douglas Harper's Etymology Dictionary
past tense of sink (q.v.).