user: Question: List all dates of succession in the state class Missouri (3).
Columns: ['State (class)', 'Vacator', 'Reason for change', 'Successor', 'Date of successors formal installation']
Types: ['text', 'text', 'text', 'text', 'text']
Sample row: ['Missouri (3)', 'Vacant', 'Did not take seat until after Congress commenced', 'Waldo P. Johnson (D)', 'March 17, 1861']
SQL:

assistant: SELECT "Date of successors formal installation" FROM "Table" WHERE "State (class)" = 'Missouri (3)';