user: ### NOW ANSWER:
Question: What is the Took Office Date of the Presidency that Left Office Incumbent?
Columns: ['Presidency', 'President', 'Date of Birth', 'Took office', 'Left office']
Types: ['real', 'text', 'text', 'real', 'text']
Sample row: [1.0, 'Robert Guérin', '1876', 1904.0, '1906']
SQL:

assistant: SELECT SUM("Took office") FROM "Table" WHERE "Left office" = 'Incumbent';