user: Question: What is the earliest Year for 400m h Event with 54.86 in Notes?
Columns: ['Year', 'Competition', 'Venue', 'Position', 'Event', 'Notes']
Types: ['real', 'text', 'text', 'text', 'text', 'text']
Sample row: [1981.0, 'European Junior Championships', 'Utrecht, Netherlands', '3rd', '400m h', '57.45']
SQL:

assistant: SELECT MIN("Year") FROM "Table" WHERE "Event" = '400m h' AND "Notes" = '54.86';