user: Question: What was the average finish when the average start was 18.4?
Columns: ['Year', 'Starts', 'Wins', 'Top 5', 'Top 10', 'Poles', 'Avg. Start', 'Avg. Finish', 'Winnings', 'Position', 'Team(s)']
Types: ['real', 'real', 'real', 'real', 'real', 'real', 'text', 'text', 'text', 'text', 'text']
Sample row: [1991.0, 2.0, 0.0, 0.0, 0.0, 0.0, '35.0', '22.0', '$27,625', '55th', '#90 Donlavey Racing']
SQL:

assistant: SELECT "Avg. Finish" FROM "Table" WHERE "Avg. Start" = '18.4';