user: Question: What is the total year with a Position of 12th?
Columns: ['Year', 'Competition', 'Venue', 'Position', 'Event', 'Notes']
Types: ['real', 'text', 'text', 'text', 'text', 'text']
Sample row: [1992.0, 'World Junior Championships', 'Seoul , South Korea', '6th', '100 m', '10.57']
SQL:

assistant: SELECT SUM("Year") FROM "Table" WHERE "Position" = '12th';