user: ### NOW ANSWER:
Question: What is the year with a Kurtis Kraft 500A chassis?
Columns: ['Year', 'Entrant', 'Chassis', 'Engine', 'Points']
Types: ['real', 'text', 'text', 'text', 'real']
Sample row: [1950.0, 'Bowes Racing Inc.', 'Lesovsky', 'Offenhauser Straight-4', 0.0]
SQL:

assistant: SELECT SUM("Year") FROM "Table" WHERE "Chassis" = 'Kurtis Kraft 500A';