user: Question: Name the sum of year for 2nd position for Junior race
Columns: ['Year', 'Competition', 'Venue', 'Position', 'Event']
Types: ['real', 'text', 'text', 'text', 'text']
Sample row: [2005.0, 'World Cross Country Championships', 'St Etienne , France', '2nd', 'Junior race']
SQL:

assistant: SELECT SUM("Year") FROM "Table" WHERE "Position" = '2nd' AND "Event" = 'Junior race';