user: Question: Name the sum of year for connaught engineering and points less than 0
Columns: ['Year', 'Entrant', 'Chassis', 'Engine', 'Points']
Types: ['real', 'text', 'text', 'text', 'real']
Sample row: [1950.0, 'Enrico Platé', 'Maserati 4CLT/48', 'Maserati Straight-4 s', 5.0]
SQL:

assistant: SELECT SUM("Year") FROM "Table" WHERE "Entrant" = 'connaught engineering' AND "Points" < 0.0;